Processing DNA scenes brought new packaging of latent powders and brushes, designed for one-time use. These should be incorporated into hazmat investigations, too, permitting their disposal upon completion of the investigation. Latent lifts must be individually packaged in plastic, warning labels attached after decontamination to protect latent fingerprint examiners from exposure to any contaminants they may have absorbed. Sturdy evidence with no further need of laboratory analysis may be decontaminated. Other materials may have to be bagged and sealed in clear plastic, to permit decontamination, and then marked to warn against being opened.
Any evidence for further exam or analysis requires special handling. Latent lifts or questioned documents must be packaged in clear bags (nylon fire debris bags are excellent), with appropriate markings placed on them after passing through decontamination to protect all off-site personnel. Materials for chemical or biological analysis require not only safe packaging on-scene, but also knowledgeable lab personnel and appropriate facilities to safely sample the evidence.
Evidence disposal is also unique. All contaminated evidence must be disposed of through approved hazardous waste handlers. Here, an agency may find guidance from local environmental authorities familiar with local hazardous waste firms. It is also important to recognize that hazardous waste disposal generates considerable expense, but nowhere near the financial cost and coast to public relations of improper disposal.
We have entered a new day in law enforcement, where techniques from both the industry and the fire service need to be incorporated into operations.
To expect the fire service, environmental regulators, or even other arms of the police service to handle contaminated scene investigations that require in-depth criminalistic services is not only unreasonable, but a prescription for flawed and failed cases. Your agency may find that investing in training and some equipment, and by strengthening the bonds among various public safety fields, pays significant dividends in the long run.
Retired law enforcement officer Paul Laska specialized in criminalistics and bomb disposal. Reach him through his website, www.paulrlaskaforensicconsulting.com.