I am afraid of failing a polygraph when telling the truth. I am scared that i will be too nervous and fail. Should I not take the test?
You are almost certainly best off not taking the "test." Polygraph "testing" is junk science (https://antipolygraph.org/articles/article-018.shtml), and it is commonly used as a coercive tool in interrogations. In particular, if you are suspected of a crime, you would be wise to get a lawyer and not speak with police without your lawyer present.
thanks for your help. I will try to avoid taking the polygraph if possible. Is there any way a truthful person can ensure that they "pass"?
While countermeasures may reduce the risk of a false positive outcome, they cannot ensure that one will pass. It is foolhardy for anyone suspected of a crime to submit to a polygraph interrogation.
I am trying to prove my innocence and that police and detectives have lied. I don't know what else to do since it is my word against theirs and i was hoping a polygraph would help show that I am being truthful and that in turn, they are not. How else can i show that I am being honest and law enforcement is not?
You don't have to prove anything to them; the burden of proof is not on you. OMERTA!