Crime Scene

Written by Dr. D. Rao


Crime Scene Investigation


Basic Rules: For evidence to be legally accepted by the courts:

  1. it must be obtained in a legal manner.
  2. It must be relevant to the issue.
  3. The chain of custody of the item must be intact and known
  4. It must be evaluated by qualified experts.

At the Scene: The recognition, identification and protection f evidence is very important. This may require complete notes, photographs, x-rays, rubber gloves, syringes, needles, forceps, scissors, knife, and proper containers adequately labeled and identified. Plastic vials and jars are useful for small samples, e.g. hair, bullets, blood and organs. Plastic bags are useful for organs, clothing and larger articles, and to cover the hands or other parts of the body. Larger plastic containers may be used for bodies.

  1. Do not alter anything of medico-legal value.
  2. Examine clothing before removing from the body; then remove and preserve any loose items.
  3. Do not cut, tear, or alter clothing.
  4. Do not put objects through defects in clothing or wounds.
  5. Allow wet clothing to dry in shade.
  6. Identify and collect adequate samples.
  7. Use clean containers.
  8. Store and transport specimens properly.
  9. Provide information and adequate instructions in regard to specimens so as to assist and direct the expert in examination a d evaluation of laboratory findings.
  10. Preserve all medicinals and suspicious substances found on and about the body and at the scene.
  11. Do not unite knots or cut material; make notes so that reassembly is possible.
  12. Evaluate all the evidence before making conclusion.
  13. Do not place more than one article in a container.
  14. Photograph any ligature before removal, cut if necessary, leaving the knot or knots intact. The cut ends may be joined with string,
  15. Handling of weapons may destroy fingerprints and blood stains and remove hair, fibres, and other trace evidence.
  16. Leave fire arms in the condition they are found. Note position of each bullet and casing.
  17. Bullets, etc, should be marked for identification.
  18. The scene should be examined by fingerprint examiner followed by a trace evidence specialist.
  19. Transfer the body to the mortuary preferably in a plastic bag, taking care to avoid producing artificial injuries.
  20. Free hair, fibres or other foreign matter which is likely to be dislodged when the body is moved should be searched and removed with adhesive tape.
  21. If there are any bite marks they should be swabbed for saliva with a cotton wool swab moisten with saline.
  22. The pubic hair should be combed in cases of sexual assault, and loose hair collected.
  23. In cases of rape and suspected criminal abortion, vaginal swabs should be taken. In suspected abortion an absorbent pad should be strapped over the vulva to collect any fluid which may run out during transfer of the body.

At the autopsy:

  1. Identify and photograph the body.
  2. Describe clothing, jewelry and other articles found on the body. Clothing should be examined for trace evidence, tyre marks, patterned abrasions and object imprints.
  3. Remove clothing without cutting or altering. If it is to be retained, it should be allowed to dry in air.
  4. Take X-rays if necessary. Any bullets or other foreign objects removed from the body should be placed into containers and labeled,
  5. Any bullets or other foreign objects removed from the body should be placed into containers and labeled.
  6. Obtain samples of hair from the head and pubic area and fingernail scrapings or clippings.
  7. Blood and other specimens should be put into clean, dry labeled containers. Use 1% sodium fluoride as a preservative for blood and refrigerate.
  8. Keep a written record of transfer of the specimen.
  9. Do not place more than one article in a container.

To maintain chain of custody, evidence should be transmitted in the following form.

Case reference: Date:
Item: Signature of holder
(Bullet, Case reference: iscera,etc) Signature od recipient
Transferred to  


1. From body of the diseased.

The biological samples should be collected in following priority order in case of dead person.

a. Skeletal muscle (deep muscle) / Tissue – The concerned M. O. should collect the least decomposed portion of the tissue and it as soon as possible to avoid further decomposition.

b. Tough tissue – If the decomposition has already started collect the tougher tissue for which the decomposition rate is comparatively slow.

Following types of tissue are observed to have lesser degree of decomposition.

  1. Muscle tendons
  2. Foot i.e. heel skin
  3. Scalp skin
  4. Palm skin
  5. Stomach wall

c. Tooth – Forward all the teeth present with the body.

d. Scalp hair with roots – Forward bunch of scalp hair with roots. Pluck the scalp hair don’t cut them with scissors.

e. P. M. Blood.

f. Bones – If the skeletonisation of the deceased is complete and no tissue or other options are available, then the longer bones of the body such as Femur should be forwarded. If some dried tissue or tendons are stuck up with the bones, then do not remove it, as there are some chances to get the DNA from it.

2. Crime scene and other Exhibits –

a. Blood stains – In murder, attempt to murder and other related cases, blood stained, clothes, scrapings, blood stained weapons and other related exhibits should be forwarded as per the requirement.

b. Semen stains – In rape cases, clothes of victim and accused, clothes at crime scene, condoms and other related exhibits should be forwarded.

Mode of parcel and proper preservatives for respective samples.




Mode of parcel



Tissue, Muscle

piece scalp skin etc.

Put the sample in clean, sterile plastic or

glass container add the preservative as recommended. Bring the sample in ice.

DMSO or Normal physiological saline or 4% EDTA solution or keep the tissue as it is in  –20 0 C refrigerator.



Clean sterile glass vial for P.M. blood. For control blood samples, tubes are supplied by FSL. Bring the samples in ice.

4 % EDTA



Air dry all the teeth available, put them in dry, clean and sterile plastic or glass container and forward.

No preservative


Scalp hair

Air dry the sample, put in dry, clean and sterile plastic or glass container and forward.

No preservative



Air dry and wrap in clean brown paper. Do not macerate or treat with any chemical. If the tissue or tendon is stuck up to the bone, keep as it is, do not separate or disturb it.

No preservative


Blood stained clothes and scrapings

Air dry the clothes and wrap in clean brown paper. Don’t pack clothes in wet or semi wet condition. In case of blood stains on the wall, scrap with a clean new razor blade. While scraping, take the precaution that paint on the wall does not mix with the blood. Put the scrapings on clean piece of paper and prepare the packet.

No preservative


Semen stains

Air dry the clothes and wrap in clean brown paper. Do not pack clothes in wet condition. In case of used condom, reverse it carefully to bring its inside out, empty it’s contents on a clean dry & sterile piece of cloth. Dry the cloth and forward. Also dry the condom pack in a brown paper and forward.

No preservative

Responsibilities of Forensic Pathologist


At scene call police and work in cooperation with them.

He can proceed with investigation along following lines

  • The Log and Documentation of the Facts
    • date and time of case, Name of person calling. The address and point of place whenever body is found / produced for autopsy.
    • Background information and circumstance of death,
    • All opportunities utilized to proceed immediately to the scene.
    • In preparing for investigation it is advisable to carry a kit with the following articles
    • Note book and pen
    • Camera with films and flashbulbs
    • Syringe with 4 inch. Size 15 needle and containers
    • Thermometer with temp ranges of 0o to 120o F
    • Measuring tape
    • Pair of gloves
    • Small plastic bags and labels
    • Flashlight
    • Stethoscope
    • Obtain information about the circumstances of death and the background of descendent
    • Make observation about the overall scene
    • Photograph the scene and the body, before any thing is moved, and if indicated after the body is moved
    • Examine the body carefully, Collect evidence like fingerprint,Nails scrapings,Swabs,Clothes,Weapon etc
  • IDENTIFICATION If skeletal/Decomposed, look for evidence such as personal effects. Wallet, paper, materials from pockets of the decedent cloths. If not make further inquires and a complete autopsy should be carried out.
  • TIME OF DEATH Circumstances of death + taking the scene along history of the where about of the decedent + factors affecting changes in the body

After measurements and the photographs are made and the finger prints taken, the weapon, if found at the scene, shall be taken into custody and placed cordially in a container. Other materials and  evidential values such as hair, nails and objects, clothing on which there are stains should be collected in sample quantity and retained in transparent plastic bags. In a case of suspected  poisoning. The bottles, boxes, vomit and even fecal matter of the scene should be all- labeled chain of custody maintained.

If death due to natural retain blood and urine samples-poisoning.