"Neither am I asking you to be a stool pigeon," said the detective.
If I were to guess at it I should say he was a detective's stool pigeon.
Was Reese merely a "stool pigeon" or was he an "agent provocateur?"
Of course, it was possible that Kurt was a stool pigeon, leading him on as a test.
"Which one of you is the stool pigeon," came the harsh query.
When the stool ...