What are the two common methods of identification used in forensic investigations?

What are the two common methods of identification used in forensic investigations?

• A. Documentary and Analytical
• B. Visual and Chemical
• C. Preliminary and Final
• D. Confirmatory and Presumptive

Answer: (D)

In forensic identification, tests fall into two common methods: presumptive (screening) tests and confirmatory (definitive) tests. Presumptive tests are quick and inexpensive, giving an initial indication that a substance may belong to a particular class. They’re useful for guiding the investigation and deciding what to test next, but they aren’t definitive—they can yield false positives or false negatives. Confirmatory tests are more specific and validated to positively identify a substance, often using instrumental analysis (such as GC-MS, FTIR, or DNA analysis). These provide conclusive results that can stand up in court. So, the best choice highlights this two-tier approach: an initial presumptive step to flag possible substances, followed by a confirmatory step to establish exact identity.

In forensic identification, tests fall into two common methods: presumptive (screening) tests and confirmatory (definitive) tests. Presumptive tests are quick and inexpensive, giving an initial indication that a substance may belong to a particular class. They’re useful for guiding the investigation and deciding what to test next, but they aren’t definitive—they can yield false positives or false negatives. Confirmatory tests are more specific and validated to positively identify a substance, often using instrumental analysis (such as GC-MS, FTIR, or DNA analysis). These provide conclusive results that can stand up in court. So, the best choice highlights this two-tier approach: an initial presumptive step to flag possible substances, followed by a confirmatory step to establish exact identity.