Evidence Collection Handbook - COLLECTION OF PHYSICAL EVIDENCE

While the specifics of collection of different types of evidence will be discussed later under the individual categories of evidence, certain general rules must be kept in mind.

  1. All evidence must be collected legally--either with a warrant, with the consent of the owner or incidental to an arrest.
  2. All evidence must be safely collected, packaged, stored, and transferred. This is of special concern with respect to bloodborne pathogens. Exposure to HIV (the AIDS virus) and to the hepatitis B virus is of much concern in collecting any evidence that has blood or other body fluids present in either the liquid or dry state. This includes garments, syringes, and other types of evidence involved in murders, rapes, assaults, burglaries, and drug offenses. Please consult your agency's exposure control plan for bloodborne pathogens. In general, at least disposable gloves should be used in handling such evidence, and safety glasses, surgical masks, and other safety garments should be available if necessary. A 10% solution of household bleach and water is a good disinfectant for cleaning items or areas contaminated by such materials; however, do not use this solution on the evidence itself unless instructed to do so by the laboratory since it could destroy some of the evidence that should be analyzed.
  3. The evidence must be described in notes. Where it was located, the circumstances, and how it was obtained should be recorded along with the date.
  4. The evidence must be marked for later identification. Initials and date, with proper notes, are usually sufficient. The use of a case number is highly recommended. Markings should be placed on the evidence itself; however, in cases of liquids, powders, small fragments, etc., the containers should be marked and sealed. The recommended places on specific types of evidence will be discussed under each particular type of evidence
  5. All evidence should be stored in a secure place with restricted access. The chain of custody should be documented. The laboratory report will include the information concerning from whom the evidence was received at the laboratory and how it was returned or if it was kept at the lab for pickup by the investigating department.

Packaging.

Select suitable containers such as round pillboxes, glass or plastic vials, or a folded paper packet (see Appendix B), paper bags, strong cardboard boxes, etc., for packaging evidence. Each piece of evidence should be individually packaged to avoid any possibility of cross contamination. Special care must be taken not to package samples with wet stains until they are dry and then NEVER IN PLASTIC. Please see the "Blood and Other Body Fluids" section for more specifics for this type of evidence. The package should be sealed, preferably with evidence tape, and initialed. Please minimize or eliminate the use of staples since they can tear disposable gloves and skin tissue and be a source of infection. Keep the chain of custody as small as possible. Keep the sealed evidence under lock and deliver it as soon as possible to the nearest laboratory providing the services needed. 

Any evidence that is a possible source of infection, especially from bloodborne pathogens (e.g., HIV or Hepatitis B virus), must be packaged in a safe manner and properly marked identifying the contents as a biohazard. Such evidence includes garments with stains of blood and other body fluids, syringes, razor blades, knives, and contraband from body cavity searches. Sharps (e.g., razor blades, knives, or broken glass) must be packaged in puncture-resistant containers with biohazard labeling. Any piece of evidence that is likely to spill due to breakage, such as a tube of blood, must be double packed to prevent spillage. For instance, blood alcohol kits and sexual assault evidence collection kits have Ziploc plastic bags for containing any blood spilled from broken blood sample tubes.

Delivering Evidence to the Laboratory.

The evidence should be sent to the laboratory as soon as possible. Use Appendix A for determining the nearest laboratory providing the services desired or call the closest laboratory and ask for that information. If the evidence cannot be delivered in person, the evidence should be sent by registered mail or certified mail.

Parcel post and regular mail cannot be traced and are not recommended. When evidence is mailed to the lab, mark the package to the attention of whatever section (Chemistry, Serology, Firearms, Documents, etc.,) to which it would be assigned. Again, please check the section in the manual covering the particular type of evidence in question. It should be noted that evidence requiring latent print work only should be sent to the AFIS Section and not the Crime Laboratory (see Appendix A). An envelope containing the KSP laboratory request form should be taped to the outside of the package used for mailing.

The Laboratory Request Form:

The completed KSP Laboratory Request Form should accompany all evidence submitted to the laboratory. The form is available at all laboratories and at the various State Police posts throughout the state. A copy of this form is in the back of this manual.

 

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