Medico-legal autopsy in rape murders

In the investigation of Rape Murders, a complete autopsy should be done. Special attention should be paid to:

1. Visit the scene of crime
2. Confirm sexual activity
3. Determine physical violence
4. Determine cause of death
5. Obtain specimens for laboratory examination
6. Take photographs of evidential value.

Scene of Crime: Undisturbed photograph or sketch of the scene is important. A record should be maintained of the state of the clothing, e.g., in disarray or skirt pulled up, and blouse, petticoat and knickers torn.These should be examined in good light for stains of semen, blood, mud, or glass and retained after air drying for further examination by forensic science laboratory (FSL).

 Sexual Activity: The presence or absence of seminal and blood stains about the legs and vagina should be observed. If dry, they should be scraped with a clean, blunt scalpel and preserved for examination. The public hair should be examined for matting from seminal fluid or blood, and for foreign hair. If the hairs are matted together, a portion must be cut off and kept for examination. The pubic hair should also be combed out to collect non-matching male pubic hair and a comparison sample of plucked hair preserved for laboratory examination.

The vagina and cervix should be examined in good light using a vaginal speculum. Normally, sperms remain motile in the vagina for about 2-3 hours and in the uterine cavity for 3-5 days. Non-motile forms may be found in the female genital tract for about 3 weeks to 3 months or more after death. To demonstrate the presence of sperms, 10-20 ml of normal saline is instilled in the posterior fornix and vaginal contents aspirated by means of a blunt-ended pipette. A wet preparation is then madeon a slide and examined under a microscopefor motile sperms. A smear is also made from the vaginal contents, fixed by gentle heat, stained by Ziehl-Neelsen’s method, and examined for the presence of sperms and smegma bacilli.

The sperm is identified by a head, neck and tail. The inexperienced may confuse trichonas vaginalis, fibres, leucocytes and degenerating epithelial cells with sperms.At least one complete sperm with head, neck and tail must be identified. Opinion should not be based on fragments. The absence of sperms from the vagina does not mean that sexual intercourse has not taken place. It may be due to non-emission, aspermia, previous vasectomy, post-supra-public prostatectomy or very old age. The presence of smegma bacilli is suggestive of coitus. Its absence is without any significance. Smegma bacilli is seen as an acid fast rod shaped organism thicker than the tubercle bacillus.

The smears from vaginal aspirate should be examined for acid phosphatase activity also. It should be strongly positive to indicate the presence of semen. If it is strongly positive but sperms are not identified, the smears should be re-examined.Smears are also prepared by taking swabs from the mouth including pharynx, and rectum and examined for the presence of sperms and acid phosphatase as with vaginal specimens. A culture for gonococcal organisms should also be made.

Physical Violence:

(Genital) Victims of rape may be of any age. The vulva, hymen, vagina and perineum should be examined for any injuries. To determine the degree of hymenalrupturing and whether this is recent or old, a glass or plastic globe.If possible trans-illuminated, may be introduced into the vagina and partially withdrawn to display the edges of the hymen on its periphery. Signs of recent rupture are ragged tears in the hymen with lack of epithelial healing, oedema and haemorrhage. Severe genital injury resulting in perineal tear and haemorrhage is common when the victim is a child or an elderly woman;such injury is not commonin mature premenopausal women accustomed to sexual intercourse. Severe injury of the vagina or uterine cervix in such a woman suggests that a foreign object, e.g.bamboo stick, bottle, or some other article has been introduced forcibly into the vagina.

(General) When clothes are torn during struggle, corresponding injuries to the body may be present and should be looked for. The whole body is then examined for marks of violence, especially abrasions on inner aspect of thighs and defence injuries. Scratches or bruises found about the cheeks, lips, neck, chest, breasts, arms or legs may have been inflicted in an attempt to stifle the victim’s cries for help or struggling, or from contact with the ground. The breasts may be shown bitten nipples or injuries.The victim should be carefully examined for evidence of strangulation. The various injuries on the body should be described in full like any other injuries, and documented by photographs or sketches.

Cause of Death: Death may occur from shock due to fright or from haemorrhage due to injuries to genitals and perineum. Death may occur from suffocation if mouth and nostrils are closed by the hand or cloth to prevent crying or shouting. Victims are often killed by strangulation. Victims of rape murder frequently show evidence of extreme violence (over-kill). This implies trauma by several mechanisms, and/or excessive and repetitioususe of the murder weapon; multiple causes of death are not unusual.

Laboratory specimens: Specimens from laboratory examinations include:

1. Scraped strains
2. Blood for typing, alcohol and drugs
3. Mated pubic hair and plucked hair samples from head and pubis
4. Fingernail clippings or scrapings
5. Vaginal, Anal (Rectal), oral or other swabs as indicated
6. Gastric contents, bile, urine or other appropriate specimens for toxicologic analyses
7. Clothes for stains

Seminal stains on clothing or vaginal aspirates may be suitable to determine the blood group of the assailant. Approximately 80% of men are secretors of blood groups substances in their semen.

Photographs: A certain minimum number of photographs is essential:

1. Undisturbed scene
2. For identification of body
3. To document injuries
4. To demonstrate any important observation

By: Navin Kumar Jaggi & Gurmeet Singh Jaggi