Which preposition to use with courtrooms

by Occurrences 1%

But we could not exchange two words, for he entered the courtroom by one door and I by another.

into Occurrences 1%

They felt they were hearing something worth while, as indeed they were, and they forgot all about Angelo and the unfortunate Crocedoro in their admiration for Mr. Tutt, who had lifted them out of the dingy sordid courtroom into the sunlight of the Golden Age.

of Occurrences 1%

Ain't it hell?" CHAPTER III THE THING THEY CALLED JUSTICE Jack stared meditatively across at the young fellow sitting hunched upon another of the boxes that were the seats in this tent-jail, which was also the courtroom of the Vigilance Committee, and mechanically counted the slow tears that trickled down between the third and fourth fingers of each hand.

under Occurrences 1%

It was further ordered that no one be allowed to leave the courtroom under any circumstances.

Which preposition to use with  courtrooms