Sexual Assault Medical Forensic Examinations
Prompt exam to minimize loss of evidence
Examine patients promptly to minimize the loss of evidence. Evidence can be lost from the body and clothing through a number of mechanisms. For example, degradation of some seminal fluid components can occur within body orifices, semen can drain from the vagina or wash from the mouth, sperm can lose motility, bodily fluids can get washed away, and dried secretions and foreign materials can fall from the body and clothing.[1] Prompt examination also helps to quickly identify patients’ medical needs and concerns.
Recognize that evidence may be available beyond 72 hours after the assault. In recent history, 72 hours after a sexual assault has been considered a guideline to use as an outside limit for obtaining evidence for the evidence collection kit. Research and evidence analyses indicate that some evidence may be available beyond this time period. For instance, sperm might be found inside the cervix after 72 hours and urine may reveal traces of certain drugs up to 96 hours after ingestion. Some examples of situations where evidence may be found even after considerable periods of time include when patients complain of pain or bleeding, have visible injuries, or have not washed themselves since the assault, or where there is a history of significant trauma from the assault. Some jurisdictions have extended their standard cutoff time beyond 72 hours (e.g., to 5 days or 1 week).
Due to the stability of DNA and sensitivity of tests, advancing DNA technologies also continue to extend time limits. These technologies are even enabling forensic scientists to analyze stored evidence from crimes that occurred years before.[2] Such breakthroughs demonstrate the importance of collecting all possible evidence.
Go to the Next Section: Timing Considerations for Collecting Evidence > Decisions made on a case-by-case basis
Download printer-friendly versions
