PLASTIC AND TAPE EVIDENCE

Also see
Glass and Plastic

 

Plastics are composed of polymers that are manufactured into a variety of different objects. Plastic evidence that may be encountered includes broken vehicle reflectors, smears on clothing, and small pieces of plastic from tapes and garbage bags.

 

Laboratory examination may be able to determine the type of plastic and whether or not it is similar to a suspected source. For large, rigid plastic pieces (e.g. broken reflectors), the laboratory can attempt a physical match.

 

Plastic fusion marks might be present on an individual’s clothing as a result of a high-energy impact with a plastic component of a vehicle interior. Because a variety of different plastics may be present on the interior of the same vehicle, it may be possible to establish the position of the individual within the vehicle by comparing the plastic fusion mark to standards from the vehicle interior. Remember that a high-energy impact can cause a plastic component in a vehicle interior to have fibers or a fabric impression from the clothing, as well.

 

Plastics and the adhesive side of tape can also be processed for fingerprints. 

 

Collection of Plastic Evidence

Large, rigid plastic pieces may be collected and packaged into paper envelopes or bags, plastic bags, or cardboard boxes.

 

Items seized for fingerprint processing must be packaged in a manner that will protect the adhesive side.  A quality wax paper will usually provide sufficient protection.

 

Small pieces of pliable plastic evidence (e.g. tape pieces, piece of garbage bag, etc.) should be placed into a paper envelope. Tape pieces that are adhesive should be affixed to a clear plastic sheet, not to a piece of paper, prior to packaging.

 

Clothing with possible plastic fusion marks should be packaged separately into paper bags.
 

EVIDENCE OFFICER PROCEDURES

STORAGE

  1. Ensure proper packaging; refer to the example board in the evidence processing areas.

  2. Place one barcode on the item and the corresponding barcode on the property receipt.

  3. Place the item in a location best suited to the size of the item, and area specified by the evidence room guide.

  4. Using the barcode reader, scan the location of the shelf and then scan the barcode that is affixed to the item.

  5. Place the item in numerical order by case number.


DISPOSAL

  1. Upon authorization or disposition of the case, see ‘General Disposition of Items.'

 

 

Revised 03/11/05