This is spot on. I'm not a protest guy myself, but I've been front and center to many National and International protests. Most were benign, but some got out of hand. Don't even expose yourself to that kind of risk when you have something to loose. Facts, data, and dispassionate discourse with decision makers is and has always been the most effective way to drive change. I.E; Sierra Club vs. Green Peace vs. Earth First. Just FYI.

To answer your question, i don't think one will matter as long as you own up to it. Make it a "political statement" during the interview and it will probably be a problem. Remember, the employer doesn't know you any better than you know them. All they see is one guy with a record and one guy without. The guy that learned his lesson and is remorseful stands a chance...the guy that isn't.....