Appendix F: Canadian Guidelines on Sexually Transmitted Infections – Forensic evidence, services and laboratories

Section VII

Appendix F: Forensic Evidence, Services and Laboratories

Forensic Evidence

  • Forensic evidence is invaluable in supporting the testimony of victims of sexual assault.
  • The purpose of forensic analysis of specimens is to establish one or more of the following:
    • That there was some form of association between the victim and the accused.
    • That sexual contact occurred.
    • That the assault was violent or forceful, thereby indicating lack of consent.
    • That the victim may have been drugged.
  • Types of forensic analyses most useful in sexual assault are as follows:
    • Identification of semen or other bodily fluids.
    • Forensic DNA analysis.
    • Hair examination (suitability for DNA analysis).
    • Textile damage assessment.
    • Examinations involving fibres and other types of trace evidence.
    • Drug screen (including alcohol) in bodily fluids (blood and urine).
  • In some situations, it may be impossible to collect certain specimens for forensic analysis. The availability of specimens depends on the sex of the perpetrator, the nature of the molestation (fondling vs. penetration) and the time between the event and the examination. An interval of more than 48 hours or cleansing the sexually abused areas will reduce the availability of specimens and the strength of forensic evidence.
  • When specimens are being collected as forensic evidence with the objective of establishing the identification of the perpetrator, certain strict guidelines must be followed. This is essential if the information gathered is to be unequivocally accepted in court. Particular attention must be paid to the manner of collection, the labelling and identification of individual specimens, and obtaining signed specific consent forms. For details on the collection of specimens for forensic analysis, local police authorities should be consulted (see Forensic Laboratories, below).
Collection of specimens
  • Physicians should familiarize themselves with the test kit before they need to use it.
  • Sexual assault examination kits differ by jurisdiction. An approved sexual assault examination kit should be used for the collection of specimens. Local practices and the instructions contained within the sexual assault kit should be carefully followed.
  • An attempt should be made to obtain specimens of seminal fluid (pristine material) from all possible sites with sterile cotton swabs. The swabs should then be allowed to air dry. The forensic laboratory will examine these specimens for the presence of semen and conduct DNA typing.
  • Any residual fluids from affected areas, such as the vaginal vestibule, should be collected by aspiration. A sterile eye dropper is ideal for this purpose in children.
    • Before aspiration, the area should be moistened with 1–2 mL of sterile saline.
    • Depending on local policies and the availability of appropriate equipment and training, samples can be examined for the presence of motile sperm. A positive finding suggests that the sexual activity occurred less than 6 hours previously. Confirmation of the presence of spermatozoa by the forensic laboratory is essential.
  • Demonstration of saliva on the body or clothing of the person who has been abused or assaulted may provide valuable forensic evidence.
    • Samples from the body can be collected with a sterile cotton swab. The swab should be moistened slightly with distilled water and rubbed over the affected area of the body. The specimen should be allowed to dry and then packaged and labelled.
    • If a child or adult is unclear about which area(s) is (are) affected, the common target areas (the neck, breast, belly, genital area, penis, thighs and buttocks) may be swabbed; a separate swab should be used for each area and labelled accordingly.
  • Judgment is required in deciding whether these investigations are sensible. It is pointless to collect such samples if weeks have elapsed since the incident or if the critical areas have since been bathed.
  • The body and the clothing worn at the time of the incident may contain trace evidence (foreign material left by the perpetrator). Items commonly encountered include hair from any part of the body, clothing fibres, lubricants, petroleum jelly and lipstick. Any suspicious hair or fibre material found on the body of the person should be removed with forceps, folded in a piece of clean paper and put in a separate, properly labelled envelope. Suspicious material such as lubricants, petroleum jellies and lipstick on the body of the person should be removed using a sterile swab, then packaged and labelled. Each item of clothing worn by the person should be packaged separately and labelled.
  • If the assaulted or abused person has reached puberty, the pubic hair should be combed and the comb, as well as any free hair collected, should be folded in a piece of paper or tissue and put in a labelled envelope or placed in a plastic bag and then sealed and labelled. Hairs can be assessed to determine their body area of origin (pubic, scalp or body hair). In addition, the root portions of any hairs may be suitable for DNA analysis.
  • Fingernail scrapings/clippings should be collected if there is a possibility that the perpetrator was scratched during the incident. The forensic laboratory will examine these samples for the presence of blood and foreign DNA. Clippings can be collected using clean nail clippers or scissors, folded into a piece of paper or tissue and placed into a labelled envelope or container. Fingernail scrapings can be collected using a nail scraper and the scraper and debris folded into a piece of paper or tissue and placed into a labelled envelope or container.
Collection of known samples for DNA analysis

It is essential for DNA typing analysis to collect a known sample from the victim. A blood stain, mouth swab or pulled hair sample can be collected as a known sample from the victim following the instructions provided in the approved sexual assault examination kit. A known blood stain is the preferred sample to be collected from the victim. A known blood stain, mouth swab or pulled hair sample can also be collected using the appropriate consent sample collection kits that are available from the Case Receipt Units of the Royal Canadian Mounted Police Forensic Laboratory Services.

Collection of samples for toxicological analysis

Blood and urine samples should be collected from the victim for toxicological analyses using the blood collection tube and urine jar provided in the sexual assault kit or grey-stoppered blood collection tubes available at the hospital.

Forensic Services

  • Investigative and scientific forensic laboratory services to detect evidence of sexual assault and abuse are available throughout Canada.
  • Services are supplied by the Royal Canadian Mounted Police and by federal, provincial, regional and local agencies and police forces.
  • Current legislation on the abuse of children obliges physicians to notify local child protection agencies of such cases. These local agencies maintain close liaison with police force personnel familiar with the investigation of suspected abuse and with the availability of forensic laboratory services.
  • Physicians should not submit specimens for forensic study directly to laboratories. This should be done through police services.
  • Physicians wishing to consult scientists on forensic matters may do so by contacting the nearest laboratory.
  • Most forensic evaluations do not include tests to detect sexually transmitted infections.

Forensic Laboratories

Alberta

General Manager
Forensic Laboratory Services–Edmonton
Royal Canadian Mounted Police
15707 118th Avenue
Edmonton, AB T5V 1B7
Tel: 780-451-7400
Fax: 780-495-6961

British Columbia

General Manager
Forensic Laboratory Services–Vancouver
Royal Canadian Mounted Police
5201 Heather Street
Vancouver, BC V5Z 3L7
Tel: 604-264-3400
Fax: 604-264-3499

Manitoba

General Manager
Forensic Laboratory Services–Winnipeg
Royal Canadian Mounted Police
621 Academy Road
Winnipeg, MB R3N 0E7
Tel: 204-983-4267
Fax: 204-983-6399

Nova Scotia

General Manager
Forensic Laboratory Services–Halifax
Royal Canadian Mounted Police
3151 Oxford Street, PO Box 8208
Halifax, NS B3K 5L9
Tel: 902-426-8886
Fax: 902-426-5477

Ontario

Chief Scientific Officer
Forensic Laboratory Services–Ottawa
Royal Canadian Mounted Police
1200 Vanier Parkway, PO Box 8885
Ottawa, ON K1G 3M8
Tel: 613-993-0986
Fax: 613-952-0156

Northern Regional Laboratory of the Centre of Forensic Sciences
Suite 500, 70 Foster Drive
Sault Sainte-Marie, ON P6A 6V3
Tel: 705-945-6550
Fax: 705-945-6569

Director
Centre of Forensic Sciences
25 Grosvenor Street
Toronto, ON M7A 2G8
Tel: 416-314-3200
Fax: 416-314-3225

Quebec

Le directeur
Laboratoire de sciences judiciaires et de médecine légale
1701 rue Parthenais, PO Box 1500
Montreal, QC H2K 3S7
Tel: 514-873-2704
Fax: 514-873-4847

Saskatchewan

General Manager
Forensic Laboratory Services–Regina
Royal Canadian Mounted Police
6101 Dewdney Avenue West, PO Box 6500
Regina, SK S4P 3J7
Tel: 306-780-5810
Fax: 306-780-7571

Report a problem or mistake on this page
Please select all that apply:

Privacy statement

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: