Ideally? His home address, place of dining, where he gets gas, shops, nearest costco, medical doctor, veterinarian, cigs and beer, the essentials. Then invite him out for a beer, and discuss the current political climate, and how it can possibly be improved.
No doubt he has good ideas.
That's liberal elite thug talk. Antifa bullies and threatens... we don't. You an undercover cop or what?