Yup. In the basement (pardon the joke) of Berkely Castle. He was first starved, but this took too long, then confined in a pit full of corpses in the hope that the stench would kill him, and finally he got the point, as it were.
He had to be killed so as to leave no mark of violence.
As a reward for organising this his wife was confined to Castle Rising, where it is said her screams can be heard to this day.
A popular mode of execution for those believd to be homosexuals... it was known as Hot Collaring and involved a bone or horn tube to prevent external burning.