Bess is quite right-and back then, a witness was also required. I got 'drafted' to be just that - Landrys Cowboy Del won a driving class, was unhooked and taken immediately to a stall, deeply bedded in shavings for the purpose, that was near the entrance to the Justin. As witness, I, along with the horse's handler and the testing official, were REQUIRED to remain right there with the horse until he "performed"--thank goodness, most horses think a deeply bedded stall IS the bathroom, and it didn't take long before the cup could be held underneath him!
Back then, it was the policy to test ALL top winners, I believe.