Then the husband and wife -- who were decidedly not in a lovemaking mood -- went over to a bed which was brightly lit with a lot of candles, so that a team of surgeons and midwives could closely measure their body fluids to determine whether or not sex had been achieved. The process could take up to two hours, but much less for those lucky few with a candle wax fetish.
And of course, the surgeons and priests would watch, in case things quit being super awkward for even a second.
If the husband was successfully able to get a rage-driven shame boner, it granted him the immediate right to put his wife on blast. An anecdote from the 1681 case of Geronima Martinez de Texada v. Diego Belasco had the supervising surgeon confirm the wife's lost virginity by "swearing to Christ that she was more open than a funnel," which may be the blazingest burn ever dropped by a 17th-Century doctor. However, if a man failed his Trial by Congress, it effectively ruined him. One famous example of things going horribly wrong in an impotence trial is detailed in the account of a marquis who, despite having a wife who was known to enjoy taking the bone train to the ville du pound, decided to go to Penis Court to clear up the gossip surrounding his dick.