Question

A suspect is attached to the polygraph apparatus and asked specific questions about the crime. the questions deal with aspects of the crime only known by the police and the actual law-breaker (i.e. the type of weapon used to commit the crime). the subject's responses are analyzed to see if he committed the crime. which procedure is this?

Answer 1

I believe the answer is: Concealed knowledge test

Concealed knowledge test refers to forensic test that is aimed to reveal hidden/previleged knowledge rather than revealing a lie.
In this test, the police usually asked several trap questions which answers couldn't possibly known by other people beside the perpetrator.