The Committee also considers questions sent in by members of the FFLM and other interested parties. These are published in the FSSC’s newsletters.
You can view the questions and answers below.
July 2021 Newsletter
The Committee discussed these concerns. The detailed questions on the front sheet are very important to the forensic scientists in interpreting the results of the forensic samples taken.
The current form is used for both complainants and suspects and the FSSC decided that although it is essential that HCPs are trained in all aspects of taking samples, there should be separate forms for complainants and suspects. These have been published this month July 2021.
Unfortunately the relevant information/paperwork regarding samples is not routinely being provided to the forensic scientists. It is recognised that there are alternative versions of these forms, both electronic and paper, and this is perfectly acceptable as long as the relevant information is provided to the forensic scientist. The FME form should be exhibited with the forensic samples by the HCP and given to the officer who takes the samples from the HCP.
The Committee discussed this and felt there was a training issue and advised that it was covered in the Recommendations under skin, genital and vulval swabs.
Pens could be put through ETO treatment, however, there would be a cost implication as it would turn them into single-use items. The committee agreed it was an unnecessary expense and that it was a training issue to ensure items were cleaned between examinations.
A paper has been published on detecting male DNA on vaginal swabs in sexual assault (listed in the Evidence document) and male DNA was found on the endocervical samples in some cases of alleged digital penetration.
There was a discussion as to whether endocervical swabs should be part of the digital penetration kit and it is advised that the HCP should take the whole set of samples if possible, especially if there is a lack of clarity on the nature of the assault. The committee agreed no changes were required to the recommendations as it was a training issue.
The committee advised that the windows should be kept closed whilst samples were being taken. However, they could be opened afterwards once the samples had been bagged. The windows would need to be closed again before another examination and before the room is cleaned.
The toilet tissue should be retained for early biological evidence but this is never required for toxicology purposes.
The order of swabs taken is dependent on the agreement of the patient, the position of the person being examined, and the skill of the examiner.
It is recognised that depending on when the perianal sample is taken, it could be contaminated as the speculum is removed, and if there is a risk of contamination being introduced to the area then the perianal swab should be taken first. It is important to remember that the perianal swab needs to be a true representation as to what was there before the anal and rectal swabs are taken. If anal swabs are to be taken these should be taken first.
In summary, the order of the swabs is dependent on the individual circumstances and would need to be decided on a case by case basis. However, the order in which the samples are taken must be carefully documented.
The committee advised that although these samples were not classed as intimate samples under PACE and would not need the Inspector’s authorisation, HCPs would usually take them.
It is recommended to put both bottles in the same evidence bag and submit this to the laboratory. All the forensic science providers are set up to analyse the samples using the current bottles.
The HCP should retrieve drugs from the foreskin of a male suspect as this is an intimate search.
There is little evidence on this matter as the number of cases with self-taken swabs is still quite low (whether witnessed or not). Although there had been a slight increase in the number of self-taken swabs at the beginning of the pandemic, there was not a significant increase overall.
There was also the issue that self-taken swabs could not be interpreted as internal swabs. This had not been challenged in court as it was clearly documented that the self-taken swabs could not address penetration as a speculum or proctoscope had not been used. There was also the potential for contamination from the outside into the inside.
Anecdotally there have been a couple of self-taken swab cases being challenged in court.
January 2021 Newsletter
In an ideal world the clinician would take a blood, urine and hair sample for every case, as drugs have different detection times. The hair sample is useful in cases where the drugs would have been eliminated from the urine and blood samples. A hair sample taken at 36 hours would not be useful for toxicology purposes.
Hair samples can be taken by police or in the case of self-referral the complainant who had self-referred would have to come back to the SARC for the sample.
The Recommendations document January 2021 for the collection of forensic specimens from complainants and suspects have been amended as follows:
‘Drugs are eliminated from the body at varying rates, resulting in detection times in urine from 12 hours to over 3 weeks after use/ingestion (depending on the drug type). Drugs are stored and therefore can be detected in hair for much longer periods of time. Therefore, if the incident occurred up to 6 months prior to the examination and there is a possibility that drugs may have been eliminated from the urine, a sample of hair may be the best possibility for drug detection. It is of note that a cut hair sample is required and that it takes at least a few weeks for hair to emerge above the skin, so a sample of hair should only be collected a minimum of 4-6 weeks after the date of interest. If in doubt consult the laboratory for advice.’
It is recommended to take both blood and urine samples for testing to see if alcohol and drugs of abuse or prescribed medications are present. The police should take the urine samples as soon as practically possible, in case there is a delay with the clinician taking the blood sample.
Doctors will be aware that the GMC recently published ‘Decision making and consent’ (in effect 09 November 2020) and section 87 refers to ‘overall benefit’ to describe the ethical basis on which decisions are made about treatment and care for adult patients who lack capacity to decide for themselves.
It was brought to the FSSC’s attention that the current instructions in the RTA blood kits were incorrect as they related to an older system for taking blood rather than the new vacutainer system.
It is essential that the time the blood sample is taken is recorded on the vial as sometimes only the time the sample was sealed in the tamper-evident bag is being recorded. The timings are useful when back calculations are required.
The instructions will be updated in the RTA kits.
Addition – 26 February 2021
Please note that whilst the road traffic kits have changed in many police forces some are still using the ‘older’ kits.
The ‘older’ road traffic kits are still available with the bottle below and the previous instructions should be followed. The long label goes around the bottle so there is consistency when samples are received at the laboratory. The process of having the long barcode on the sample also standardised things with the urine containers which are again different. The time the sample is taken is ALWAYS recorded, this is a requirement in the MGDD/B, and is also written on the outer tamper-evident bag the samples are sealed in.
July 2020 Newsletter
Fingernails should be frozen alongside other samples for consistency and as there may also be body fluids on the samples these would be better preserved if frozen.
There is a huge variation in practice as to who takes the elimination DNA samples. However, recent experience suggests that although these can be taken at any stage, in some cases it will be important to have the elimination DNA sample taken as early as possible in the investigation.
The committee agreed that there was no issue with using the polypot for mouth rinse samples.
Where control skin swabs are required it is difficult to provide definitive advice as to the best site. Such decisions need to be made on an individual case basis. All HCPs taking forensic samples should be aware that if they need to discuss recovery strategies with a forensic scientist they can obtain contact details for their area Forensic Service Provider (FSP) through the police.
Practitioners advised that another kit could be opened to take all the samples that were required. It is not possible to state which samples should be prioritised as ideally they should all be taken. The FSSC recognised that sometimes it was not possible to use another kit as it depended on the police procurement and what kits they had available.
Scenesafe Stuart Wiseman thought that a new kit had been commissioned in the area and would discuss direct.
If there was a discrepancy between the samples taken then the forensic scientists would be able to investigate the matter further.
It was highlighted that the clinician would not know if the samples were taken properly by the police and the committee agreed it was a police training issue.
Some practitioners repeat the samples. If the query related specifically to urine samples – the recommendations state to take two urine samples if the incident occurred in the preceding 24 hours and one if the incident occurred more than 24 hours ago, however, some clinicians were interpreting that as an EEK was one of the urine samples.
Two urine samples were taken for toxicology so there was an ability to do back calculations for alcohol. Often a urine sample is taken in the SARC for clinical reasons e.g. pregnancy test.
The committee advised that all samples were important and should be taken.
Work is progressing on standardising kits aiming for National Modular Kits. Training for police officers is not mandatory. The College of Policing and NPCC do not have the powers to mandate police training.
The committee advised that they were not aware of any audit/research being undertaken in the area. There is some work being planned between Merseyside and Cellmark regarding samples (i.e. what samples were taken/sent to Cellmark and processed, what the results were, etc.). This is on hold because of COVID-19. It was noted that there is limited information available throughout the process from the sample being taken to conviction.
So my questions are:
If the penis has only made contact with the perineum or perianal area only (with or without anal penetration; and in the absence of vaginal penetration for female complainants) are the FFLM recommendations advising the collection of perianal swabs within 7 days?
In general, no. The advice will depend on the circumstances of the case and persistence data, and the appropriate application of the recommendations. In this case, a male, the DNA would be on the perineum and peri-anal area. If there was any degree of ejaculation or release of pre-ejaculate, then, even if sperm migrated into the anus, drainage would mean the material, including the DNA should be lost by/within 72 hours. Assuming this is an area which is warm, moist and frequently wiped, (and bacteria on the skin and within the anal canal would break down cellular material), it would seem that it is unlikely DNA would persist beyond 72 hours.
If so, what is the rationale for this? Moreover, given that if the penis had only made contact with the skin of the thigh/groin crease for example, the recommendations for skin swabbing would be 48 hours. (The same query would also arise if a complainant reports direct penile contact with only the external vulva, would perianal swabs within 7 days be a reasonable request according the recommendations).
Probably not, but again the circumstances of the case might support sampling beyond 48 hours, e.g. if the patient had not washed/wiped and been immobile, or if there was any suggestion of ejaculate being deposited, and no washing etc.
If there was penile-anal penetration of a male complainant with ejaculation onto/into the anus/perianal area, are the FFLM recommendations advising the collection of perianal swabs even from day 4 to day 7? This would mean that whilst we would not collect any anal/rectal swabs beyond 72 hours, we would, however, collect perianal swabs only from day 4 to day 7 – and is there evidence for this?
The FSSC were not aware of any evidence either way, but again thinking of the circumstances of the case, sampling beyond 72 hours would seem inappropriate. Sperm/DNA from the ano-rectum would have drained away by then and/or been broken down, +/- the effects of washing, wiping etc.
In the case of children, if the penis only makes contact with the vulva/perineum/perianum (without penetration of the anatomical vagina) are the recommendations that perianal swabs should be taken up to 7 days? This would have significant implications for paediatric forensic medical examinations.
Again, depends on the circumstances of the case. The above 72 hours would apply to boys and pre-pubertal females.
Lastly, regarding vulval swabs, the FFLM recommendations do not make a distinction for vulval swab collection for prepubertal children (cf low and high vaginal sampling) – does that mean vulval swabs should be taken for prepubertal children up to 7 days?
This decision needs to be made on a case by case basis considering the stage of puberty of the child.
Testing for nail polish remover is possible, as acetone should be detectable in blood and urine samples but testing for bleach in blood and urine is usually not possible.
There are no special requirements for the vials – the usual toxicology sample vials will suffice. Standard toxicology testing will probably also be requested so “normal” samples would be required for this – blood and urine. If possible, please collect both preserved and unpreserved blood samples.
As with all toxicology samples, it is really important to complete the FME form with as much information as possible to assist the toxicologist, such as the time interval between incident, admission to hospital and sampling if known.
The committee discussed and advised that this is a consent issue and the situation should be clearly explained to the parents so that they could give appropriate informed consent.
There is guidance in England and Wales for police working under the PACE Act please see below.
(Advice received from Detective Superintendent Jonathan Holmes from the Child Death Working Group, June 2020):
Arrest and make request in custody under s62 PACE as intimate sample (blood or urine).
To avoid arrest and custody if sole purpose is to exercise powers under Section 62 PACE, alternatively caution and obtain samples at hospital.
In case of refusal, move to arrest.
Voluntary basis only. Presumption should be that samples are sought in all SUDC reports unless circumstances suggest no practical value (e.g. teenager drowning – parents at work). Samples could be of significance in other proceedings, e.g. coronial / family law.
Points to consider:
Requests to be made with compassion and sensitivity.
Requests to be made ethically.
Use form of words provided by National Child Death Investigation Working Group.
No caution to be used (non-suspicious = not suspects).
Recommended form of words to be used for voluntary samples request
This form of words should be used where no criminal offences are suspected. The purpose of this form of words is to provide a framework that facilitates an ethical request for consensual samples. In addition, officers are asked to consider that this request be made with compassion and sensitivity and that no caution is used in making the request of parents/other relevant persons.
I now need to ask you if you are willing to provide blood or urine samples for use in the investigation into the death of your child.
You do not need to provide these samples and I have no legal power to compel this. However, these samples can assist us in investigating the tragic circumstances of a child’s death. I do need to make you aware that there are certain circumstances where the presence of drugs or alcohol can render someone liable to prosecution for criminal offences. Do you provide consent for blood or urine samples to be taken?
January 2020 Newsletter
The form has been amended to include a space for recording the number on the Tamper Evident Bag (TEB). It is essential that this form is completed by the examining HCP, exhibited, and given to the police officer with the samples. Many organisations have an in-house version of the form and the same applies. The form is essential for the forensic scientists to be able to interpret the results.
The Government has responded (see link below) recommending that the Forensic Science Regulator’s remit and resources be reformed and expanded to include responsibility for regulating the market.
Unfortunately, blood samples are arriving at the laboratories and the glass vials are broken. It is essential not to overfill the sample bottle. The current recommendations state:
Approximately 7.5 ml into 10ml/2x5ml tubes (no more than ¾ full, preferably glass).
The breakage is likely a result of expansion after freezing but cushioning of the bottle is important too. Please remember to put the foam piece/cotton wool into the plastic container that the blood sample goes into.
We obtained advice from Dr Paul Williams, Forensic Science Consultant:
All the roadside breath test devices used by the police in the UK are insensitive to ketones, so this detainee’s initial reading of 94 had to be due to alcohol. The evidential breath machine used has four channels of infrared for ethanol measurement and specificity. It will register the message ‘Interfering Substance’ if the ethanol reading is elevated by more than about 2ug due to the presence of some non-ethanolic substance in the breath. This is a requirement of Home Office Type Approval. Further, as the evidential breath machine’s ethanol measurement channel is about 20 times more sensitive to ethanol than it is to acetone anyway, it means that in the absence of ethanol [as per her claim] to score the 93 she did through undetected acetone would require a breath acetone level of around 2000ug/100ml [i.e. 20 x 93]. This would require a blood acetone level of around 650mg/100ml – some ketosis!
The detainee’s readings are therefore of course completely ‘inconsistent’ with her claim that she had not consumed alcohol.
The FFLM has discussed with, and sought advice from, a number of colleagues including forensic scientists, the Forensic Science Regulator and the Biometrics Commissioner, as well as considering the requirements of the Protection of Freedoms Act (PoFA), 2012. However, the following is not to be construed as legal advice, and colleagues may wish to seek their own – including legal – advice.
Looking at the wording of section 14 of PoFA/section 63R of PACE it appears that the situation as above is not covered by the provision requiring DNA samples to be destroyed within 6 months of being taken. The section applies to samples either taken under PACE powers (which does not appear to apply here) or taken by the police, with the consent of the person, in connection with the investigation of an offence by the police. If the person self-refers and has not yet reported to the matter to the police it would be a real push to construe the sample as having been taken by the police (or on their behalf by staff at the SARC). Further, if an offence has not been reported, the sample does not appear to be being taken in connection with the investigation of an offence by the police. This situation would not change if the offence were subsequently reported to the police, as this applies only at the time when the sample was taken.
Given the above, it does not seem that the 6 month PoFA time limit should apply to elimination samples taken by SARCs as a result of a self-referral, at a time when no report of an offence has been made to the police. Having said that, once the sample enters the criminal justice system (i.e. the person reports the offence and the sample is passed to the forensic science provider (FSP) for processing), it would seem sensible to at least respect the spirit of PoFA, even though it does not strictly appear to apply. In which case the sample should usually be destroyed after the profile is derived unless there is a specific reason for not doing so that can be justified under the Criminal Procedure and Investigation Act (CPIA), 1996 exemption. Retained samples should then be monitored in the usual way and destroyed when they are no longer required.
The current FFLM Recommendations state that hair samples should be considered:
If the incident occurred up to 6 months prior to the examination and there is a possibility that drugs may have been eliminated from the urine (drugs are eliminated from urine at rates varying from 12 hours to over 3 weeks).
It is recommended in relation to hair sampling to:
Use a suitably accredited laboratory (check that their accreditation covers hair analysis and all the drugs that you require testing for).
Check that the laboratory follows the recommendations published by the Society of Hair Testing (www.soht.org). The ‘Statements’ and ‘Consensus’ on this website contain useful guidelines for testing for drugs, alcohol
markers and doping agents in a variety of applications and investigation types, including guidance on sample collection, sample preparation and analysis, analytical method sensitivity and cut-offs and quality assurance (including proficiency testing).
Obtain a full report with interpretation of the results, taking into account any circumstances relevant to the case e.g. any limitations to the analysis/hair sample, potential surface contamination of the hair by environmental or home environment etc.
Here are some examples of how hair samples may assist:
Example 1: demonstrates past drug use when blood testing is negative
Child taken to hospital due to concerns for his welfare:
Found to have several recent and old injuries.
Parents deny abuse (or recent drug use, mother admits past cannabis use).
Blood samples taken from parents about 17 hours after police called:
No urine taken.
Tests for drugs of abuse on blood negative.
Hair samples taken from parents:
Father (3 sections, 0 to 6 cm): occasional cocaine use/exposure.
Mother (3 sections, 0 to 6 cm): cannabis use (suggests more recent than admitted).
Example 2: demonstrates investigation of explanation provided by suspect
Child taken to hospital with a suspected overdose (unconscious).
Parents stated that the child had ‘accidentally’ got hold of their antidepressant medication.
Blood and urine taken in hospital:
Positive for amitriptyline (and metabolite nortriptyline).
Positive for amitriptyline and nortriptyline in 3 sections (3 x 1cm sections)
High concentrations suggesting administration/ingestion on more than one occasion.
Example 3: demonstrates how the ‘pattern’ of drugs in the hair can provide information on the likely source and whether or not it could be due to surface contamination
Police called by Emergency Services as they were dealing with a ‘heavily intoxicated’ female:
Concerns raised about the welfare of a 2-year-old child present in the house.
Mother admitted buying drugs off the internet to help her sleep.
Hair sample taken from the child approximately 2 months later (3 sections analysed, 0 to 9 cm):
Cocaine (low) plus other metabolites including norcocaine in all 3 sections. Suggests at least some ingestion but not necessarily deliberate (could be from environment or household due to touching contaminated surfaces (including clothing/ hair, passive inhalation etc.).
Cannabis: THC in all 3 sections (plus washes) but no metabolite (carboxy-THC). Suggests environmental contamination most likely.
Diazepam (low) and alprazolam in all 3 sections. Suggests repeated exposure to alprazolam and possibly occasional exposure to diazepam (although low concentration of diazepam could also be from external contamination).
All concentrations highest in 3rd section and lowest in 1st section. Decreasing pattern.
Example 4: demonstrates usefulness in a DFSA case when there has been a significant time interval prior to urine collection
Adult female believed that her drink had been “spiked” on a night out:
Reported to police 2 days later.
Urine sample taken approximately 2½ days after the alleged incident (negative).
Denied drugs of abuse use.
Hair sample taken about 6 weeks after the alleged incident (3 sections analysed for sedatives/DOA and alleged incident should correspond to 1st section).
antidepressant drug in all 3 sections (prescribed)
GHB (8 sections): 0.8 to 1.4ng/mg (endogenous)
Cocaine and ketamine (low) in 3rd section (4 to 6cm i.e. at least several weeks prior to incident), very low ketamine in 2 earlier sections also but hair sample described as badly aligned.
Example 5: demonstrates how using both blood and hair analysis can provide a more detailed picture of past drug use
Male arrested for murder:
Blood sample taken 27 hours after incident (no urine).
Hair sample taken around the same time.
Stated he was prescribed diazepam (but not taken it for 2 days), co-codamol, a sleeping tablet and an antidepressant. Previously prescribed an anti-psychotic.
Admitted cannabis use.
Diazepam and metabolites detected (therapeutic level).
Very low level of cocaine metabolite (benzoylecgonine).
No cannabis (could be eliminated – no evidence of chronic use).
No anti-depressant detected (possibly eliminated, depending on dose?).
No tests carried out for anti-psychotic medication.
Hair analysis (3 segments (0-7cm)
Regular cocaine use (in all 3 sections)
Occasional use of other stimulants (e.g. MDMA) plus ketamine
Occasional cannabis use (low in 2 most recent sections)
Repeated codeine, diazepam and sleeping tablet use (as expected)
Occasional tramadol use
Confirmed repeated antidepressant use (plus several others!)
Confirmed antipsychotic use (higher in 2 older sections), plus another antipsychotic.
When the Police submit intimate samples to a Forensic Service Provider in relation to a sexual offence case they usually want to know if semen or other biological material is present, and whether this finding supports the view that a certain activity (e.g. vaginal intercourse) has taken place. Often a forensic scientist will have to consider two alternative propositions (e.g. vaginal intercourse with ejaculation in to the vagina vs. non-penetrative activity with external ejaculation) and determine if the findings provide support for one scenario over the other.
In order to fully evaluate findings from intimate swabs a forensic scientist will consider the nature of any material present, the amount of material/DNA detected and the distribution of material/DNA between the different areas sampled. Information from the medical examination, such as the order in which samples are taken and whether a speculum and/or proctoscope is used, will assist the scientist in determining expectations from the examinations. The use of a speculum or proctoscope will ensure high vaginal/endocervical swabs or rectal swabs do not contact external or lower vaginal/anal tract areas during sampling, thus it may be possible to address whether vaginal or anal penetration has occurred. If the FFLM recommendations for sampling are followed, then this will minimise the transfer of material from one sample area to another and help ensure the forensic scientist’s interpretation is robust. If it is not feasible to follow the recommendations then documenting this clearly, and giving reasons why, will assist the scientist.
After semen/DNA is deposited in the vagina/anus it will begin to degrade and be lost through actions such as washing and drainage. Consequently, as the time since intercourse (TSI) increases the amount of semen in the vagina/anus will decrease. Furthermore, different components within semen will be lost/degrade at different rates. Therefore, by evaluating the levels of semen present and the presence/absence of different components of semen, it may be possible to address when sexual intercourse is more likely to have occurred. Therefore, even if two scenarios are presented to the scientist which involve the same/similar activities but are alleged to have occurred at different times (as often occurs with a domestic incident) the examination of intimate swabs may still assist in the investigation.
On occasion an allegation may be made in which semen (or other material) is deposited on a specific area of the external genitalia, such as the external vulva or within/between labia, however, sampling such distinct areas separately is unlikely to assist the scientist’s interpretation of the findings. Due to the proximity of these areas any material present on one area of the external genitals will, over time, be redistributed to other external areas by actions such as drainage, wiping and contact with underwear. Therefore, sampling multiple external genital areas separately will not assist the scientist in determining which specific area any material was originally deposited. Consequently, when recovering material from the external genital area it is advised that the FFLM recommendations for areas sampled are adhered rather than subdividing into smaller distinct areas, for example, labia and posterior fourchette.
There have been a number of different versions of this certificate produced in recent years and the FFLM has been asked if this is acceptable.
There is no national template so individuals/companies/police forces can develop their own version as long as it is clear it’s a Certificate relating to Sec 16(2) Road Traffic Offenders Act 1988 and covers the relevant elements as below:
16(2) Subject to subsections (3) and (4) below, evidence that a specimen of blood was taken from the accused with his consent by a medical practitioner or a registered health care professional may be given by the production of a document purporting to certify that fact and to be signed by a medical practitioner or a registered health care professional.
January 2019 Newsletter
The FSSC meets every six months to review and revise the recommendations as appropriate.
This time there are a couple of significant changes to the recommendations. The number of penile swabs has been reduced to two. Swabbing the glans has been combined with swabbing the coronal sulcus and internal foreskin. This should be more time-efficient and cost-effective. Please take moist
and dry swabs from:
Shaft and external foreskin (if present)
Coronal sulcus, internal foreskin (if present) and glans.
There is also a new section: Urine sample for DNA. This is only recommended in exceptional circumstances when the complainant refuses a forensic medical examination.
It is essential that forensic specimens are appropriately labelled. The name of the person (examinee) from whom the specimen has been taken MUST be on the tube/bottle/container. In a sexual offence examination of a non-police referral, use the unique reference number in place of examinee’s name. The tamper evident bag MUST also be clearly labelled as per the Labelling forensic samples document.
There have been a number of queries with regard to the Forensic Medical Examination Form. This is a four-page form that was updated a couple of years ago and has been revised this month (January 2019). It is essential that this form is completed by the examining HCP, exhibited, and given to the police officer with the samples. Many organisations have an in-house version of the form and the same applies. The form is essential for the forensic scientists to be able to interpret the results.
Ideally, it is best for a blood sample for toxicology to be taken prior to a blood transfusion as there is a dilution effect for drugs. However, this is not always possible and even if a blood transfusion/other fluids have been given a blood sample could still be useful and so should be taken. As with all cases where drug-facilitated crime is suspected a urine sample should be taken by police as soon as there is the suspicion of involvement of drug and/or alcohol in the incident. HCPs should advise the police when requested to take blood that the police should take urine immediately.
Changes in temperature would affect the glue line on the tamper-evident bags, however, the temperature changes would need to be extreme in order to shorten the lifespan of the bag.
The committee advised that if no skin swabs were required, a background skin swab would not be needed.
Samples for toxicology can be kept refrigerated if submitting to the forensic laboratory within three months of collection (freezing is recommended if storing for more than three months), however, it is better to submit samples for testing as soon as possible.
Body fluid samples could be kept indefinitely if appropriately stored. Guidance is available from the relevant forensic science provider.
Any interruption to the correct/normal storage of frozen exhibits needs to be recorded in as much detail as possible (see below).
The items would still be assessed by the forensic scientist, almost regardless of the interruption. A decision would then be made about testing. In most cases the testing would go ahead, but the information about the interruption, and the visible state of the items/swabs would inform the evaluation of the findings.
In relation to toxicology samples. Some drugs are still stable at room temperature but alcohol and some drugs do degrade over time and this degradation will be quicker at room temperature. Alcohol can also be produced in samples – if certain micro-organisms are present.
There are many variables such as whether the degradation is from microbial action or simply heat, how warm the samples get, the length of time that the samples are above recommended freezer (or refrigerated) temperature, the concentration of alcohol and drugs in the sample and whether or not the degradation products would also be detected by the analysis. For most drugs, it is unlikely that a high concentration would decrease to undetectable levels but, in a case with long time intervals where there may be drugs around the detection limit, some drugs could degrade to undetectable levels.
The toxicologist would generally continue with the analysis but add caveats to the results depending on the drug suspected and the circumstances of the case. Ideally, information regarding how warm the freezer (or fridge) got and for how long would be required. Fridge/freezer monitoring should be in place and regularly checked.
Samples that are to be submitted for toxicology analysis within a few weeks can generally be stored refrigerated or frozen so, if a freezer breaks down and the temperature does not exceed refrigerated temperatures before it is noticed, then this should not be an issue.
Biological samples for DNA
The time taken from ambient storage to freezing of swabs is possibly less critical than the amount of time a sample is frozen or thawed but either way minimising extremes of temperature change is good practice.
Guidance on fridge/freezer monitoring
Monitoring the temperature of the fridge and/or freezer with a daily check recorded is essential for a complete record of temperature at which the sample has been stored including any temperature deviations. The actual acceptable temperature range appears to be governed by what is specified by the equipment manufacturer e.g. fridges operate at 2° to 8° C and freezers operate at approximately -20 °C (must be below -10 °C to maintain freezing).
Best practice is to check the freezer temperatures daily and record the reading. Action is required if the temperature deviates up or down by 5 °C. Freezers should be alarmed and there should be a backup generator. It is good practice for the equipment used for the temperature monitoring to be calibrated and its accuracy known.
It is possible where freezers have broken down or have been accidentally switched off for up to 48 hours that there may still be positive body fluid findings and DNA results.
The storage of toxicology samples is non critical i.e. it just needs to be at ‘refrigerated’ or ‘frozen’ temperatures but does not need to be at a specific temperature (as it may need to be for certain diagnostic reagents, some medications, certain foods etc).
The committee agreed that there were a number of reasons why a forensic medical examination should still take place such as the documentation of injuries and the arrangement of further treatment, e.g. emergency contraception, STI screenings. Forensic swabs may be of value depending on the time interval between the consensual and non-consensual acts.
The committee advised that swabs should still be taken and highlighted that certain sanitary products (i.e. tampons) may hold sperm internally for a longer period.
The committee discussed and advised that in certain circumstances, an out of SARC examination was the only available option. It would be important for the attending clinician to take all necessary anti-contamination precautions and document their actions.
The committee discussed and advised that it would not make a difference if the swabs were separated out and that no changes were required to the Recommendations document.
No. The committee discussed and advised that if there is a visible injury/bite mark then a skin control swab should be taken.
An unopened batch control swab is not always needed as the kit providers keep controls. It should only be taken if there was a control swab in the kit. If there is no control swab in the kit, it is essential that the batch number is noted (as per the FME form).
The committee advised that if the clinician was wearing personal protective equipment (PPE) and the cases were unrelated then they would not need to shower between each case. It was highlighted that ideally if examinations were required for the same case, a different examiner and room should be used. The risk of contamination between unrelated cases was queried and it was advised that following further investigation it may be possible to determine how contamination could have occurred between unrelated cases.
The committee discussed the importance of the clinician taking a history from the complainant and highlighted that it helped to determine further treatment.
The scientists advised that that incontinence pads are very difficult to examine as they draw in fluids and it is therefore difficult to extract DNA so there is definitely value in taking swabs to avoid loss of evidence. DNA survives in faeces and the committee advised that swabs should still be taken in such cases.
The committee discussed and advised that it was a consent issue and that the situation should be clearly explained to the parents so that they could give appropriate informed consent.
The Home Office have advised that the guidance is there because there is potential for food and drink to inhibit the production of a DNA profile from a sample, after 20 minutes the food and drink residue levels should have diminished to a point at which there should no longer be an appreciable inhibition action i.e. that would affect the production of a DNA profile.
The committee highlighted that the Recommendations state that the examining clinician must make a decision regarding obtaining samples on a case-by-case basis, as exceptions to the timescales are possible, e.g. if the examinee has been bed-bound.
This is a specialist procedure (non-urgent), as is the investigation of any infection the consequence of which may be a criminal prosecution. A strategy discussion needs to take place to include the investigating officer and the forensic clinician along with appropriate advice from a specialist clinician e.g. in virology, microbiology and infectious diseases, to ensure the correct sample is taken with the necessary arrangements in place for its storage and transport, and testing, under a chain of evidence procedure. A specialist kit may be required to take the samples.
The HCP must obtain consent for a blood sample in all circumstances. What happens in this case is entirely dependent on the police and for what the individual has been arrested. If the individual has been arrested under Section 4 driving/in charge under the influence of drink or drugs then an assessment should be performed and the police advised whether there is a ‘condition’ due to a drug. This then allows the police to request a blood sample. If the individual is arrested under another offence then samples can be taken under the usual PACE requirements for intimate samples.
January 2018 Newsletter
The committee agreed that if the examinee would only consent to self-swabbing it was better than no examination at all. However, the clinician should clearly outline the pros and cons of a full examination to the examinee first. It was also highlighted that it should be clearly documented and ideally the clinician would witness the sample/s being taken. It was agreed that the Recommendations should be updated to reflect this.
The committee advised that it was not critical who labelled the sample/s as long as the person exhibiting the sample/s checked that the labels were correct.
The committee advised that the use of the right scope was a matter of clinical judgment and whichever was used should be clearly documented.
The committee advised that cleaning was not recommended during training and that the area would only be cleaned first if there was very heavy staining.
The committee advised it was not routinely suggested and that small children would only be anaesthetised when there was a clinical justification e.g. other injuries.
The committee advised that a moistened swab was recommended as it was not a naturally moist area. It was also highlighted that a moistened swab may be required for the low vagina if the area was markedly dry so it was also a matter of judgement.
It was highlighted that the Recommendations state that if the vaginal mucosa is dry, the first swab can be moistened and with regards to the high vaginal swabs, the speculum would be lubricated. If it was not possible to pass a speculum and blind swabs were required it would be a matter of judgement for the clinician.
The committee discussed and agreed that if a venous blood sample could not be obtained, a sample could be taken from an arterial line by an ITU nurse witnessed by the clinician.
The committee discussed and advised that there was not much to be gained taking the sample after three days.
The committee discussed and advised that it was variable and dependent on the case. In the UK, the practise of taking vaginal swabs in suspected anal intercourse cases is to refute any allegations that may be made at a later date.
The committee discussed the difficulties in deciding what samples should be taken as the samples are taken on the basis of the account given by the complainant. At the stage the samples are taken, it is not known what account the assailant may give. It was highlighted that on the first page of the Recommendations, clinicians are advised to consider what samples are required on a case by case basis.
It was advised that ideally the tampon should be removed in the appropriate sequence of swab taking, i.e. after the low vaginal swabs and before the high vaginal swabs. It was added that if there had been a number of tampon changes since the incident, it would not make a difference as to when in the process it was removed. It was essential that clinicians documented what was done and when.
This question raised a number of issues and a new guidance document has been created to address them.
The committee advised that samples should be taken as there might still be traces of semen.
A glass or two of water would not make much difference to the levels of drink/drug in the urine. The concentration of drink/drug would depend on other factors such as how hydrated the individual was. However, if an individual was drinking litres of water then that would be an issue.
The committee advised that UV lighting was not an appropriate tool as it would not fluoresce all DNA sources and would fluoresce items without DNA.