"It has been threateningly said to pro-life groups over the years also, that if you or anyone who is a part of your group protests outside an abortion clinic and is arrested, we will revoke your 501c3 status."
I wasn't aware of that. But I'm sure you're correct.
The hate America crowd is encyclopedic in their knowledge of the law when it suits their purposes.
If you have some citations for this, that would be great.
I'm going from personal experience on this. I don't have any written sources I can site. Contacting National Right to Life or Operation Rescue might lead you to some documentation.