It's a shame that the summary and the article omit the most important information needed to judge whether this is reasonable or not -- details and evidence in support of the characterization of the groups Barr belonged as "linked" to the group responsible for the armored car robbery & murder. What does "linked" mean in this context: members in common? command structure? who knows? The article doesn't say, and without that information none of us can have a really informed opinion on the topic.
Since there's not much to discuss from TFA, I'm going to tell you a little story from back when I was in school, because it's conceivably relevant (but then, as I've said, we don't really have the details we need to know..
Annnnyyyyway.. Once upon a time, long ago (but still some years after this woman was in school) I was a student at the University of Michigan in Ann Arbor. During the time I was on campus there were a group of chuckleheads who fancied themselves the vanguard of the socialist revolution that was sure to sweep the country Real Soon Now (tm). They were the scourge of all of the small clubs on campus because of a trick that they pulled, over and over, quite successfully until the other student groups learned to defend themselves against it.
Here's what would happen.. A small, inoffensive campus group having little or nothing to do with the main goals of the revolutionary organization in question would have a meeting at the beginning of the year to welcome new members and to elect leadership positions for the coming school year. Let's imagine we're talking about the Campus Knitting Society.. Well, a group like that might have 8-10 members who attended meetings regularly, and a few more who would drop in when their schedules allowed. The Revolutionary Chuckleheads League (not their real name) would descend en masse on the Campus Knitting Society the week that group was electing new officers and since a lot of groups had open membership the RCL would nominate its own slate of officers and take over the Campus Knitting Society. They'd use the small budgetary stipend the group got from the student government activities fund to print up flyers and the next thing you'd know, every kiosk on campus would be covered with fluorescent orange flyers saying "U of M Campus Knitting Society DEMANDS AN END TO US IMPERIALISM" and "U of M Campus Society Says: Free Mumia!". Then the Revolutionary Chuckleheads League would abandon the burned-out husk of the club they'd taken over and move on to play the same trick on some other organization. The shellshocked original club members, if they weren't completely soured by the experience, might form a new club to replace the one that had been stolen from them, which is why from time to time you'd see flyers pop up on campus saying things like "First Meeting Sunday Night: Michigan Knitting Club (NOT THE Revolutionary Chuckleheads League)"
So.. I've got no idea from the article what Barr's politics were at the time, what they are now, and what her level of involvement with the banned group might be. But it wouldn't surprise me if there were a lot of people that I went to school with who belonged to perfectly harmless clubs who could conceivably fall afoul of the same shadow that blighted Barr's career just because they belonged to a club that got infiltrated and taken over by a group of radicals whose interests were only tangentially related to the club's original goals. I don't think that happens very often, but I would like for the government to have a higher standard than "affiliated" or at the very least to make clear what they mean by that.