Should I speak with a lawyer before taking a lie detector test?

Question Details:

Today Iwent into the local sheriff's office to take a polygraph test to prove that I knew nothing of a theft committed. But when I arrived, the investigator preforming the test pulled me into his office and asked if anyone had threatened me to take the test. I informed him that the investigator handling the case and the man who was robbed had threatened me with putting a warrant out for my arrest. So the investigator doing the test told me he would lose his licence if he gave me the test due to the fact I was being forced to take it. However, the officer handling the case is still threading to put a warrant out. What can I do? Important Notice