What is the proper technique for collecting blood splatter evidence?

Collecting blood splatter evidence requires careful handling to ensure the integrity of the sample. The correct method involves placing the blood evidence into a paper bag and allowing it to dry if it is wet. Paper bags are preferred over plastic because they allow air circulation, which is essential for drying. This helps prevent the growth of mold or bacteria that could compromise the sample's viability for analysis.

After drying, the evidence should be handled with care to avoid contamination and maintain its condition for forensic examination. The other methods mentioned may not effectively preserve the sample's integrity. For instance, using a plastic bag could trap moisture and lead to decomposition of the sample, while glass containers and freezing could introduce other issues related to sample integrity. Lastly, using a sealed envelope might not provide the necessary conditions for adequate preservation of wet samples. Thus, the use of a paper bag and the drying process is the recognized standard for handling blood splatter evidence.