I have a friend in removal proceedings?

I have a friend in removal proceedings, he is an overstay, has a master hearing scheduled next month. The good news is that he just married a USC and was told by a clerk at the court to submit a I-130 petition to the service center along with a bona fide marriage exemption. can someone please explain to me what a bona fide marriage exemption is, and when submitting one, what do i submit, is it in a form of a letter, or is there a particular form for this.