He's also a trainer for the FBI, ICE and law enforcement all over the country to conducting lie detector tests. He's also considered THE expert on reading polygraph results and has been used in courts for both prosecution and defense atty's in more cases than most judges will even see in their lives.
The mans's credibility is impecible, he never met the Ramsey's prior to administering the test either. People want to make a big deal of the fact that the Ramsey lawyers hired him to do the test. If they were so worried about the results, this would not be the person to hire to conduct them. Not, with his decades long reputation of fairness, unbiased and accurate polygraphy skills.
What makes the charge he was some how more "friendly to the Ramseys simply because he was picked by their lawyers if that the Boulder PD themselves (along with more depts than I can name) have used him in the past on other cases.
So what, they are about as accurate as a fortune teller if you ask me. They may get lucky and get it right every now and then.