When I took the bar exam in Buffalo, New York, none of my fellow test takers were arrested during the course of the exam. Those following in my footsteps this time around were not so lucky.
An ID of the suspect will not be difficult. At least when I took the exam, you had to both sign and put your finger print on your exam each test session, to insure that an imposter wasn't taking it instead. I'll bet doctors don't have to do that.