There really isn't clarity here. The article argues that the flight wasn't overbooked, therefore UA couldn't kick anyone off. I agree if it wasn't overbooked,

There really isn't clarity here. The article argues that the flight wasn't overbooked, therefore UA couldn't kick anyone off. I agree if it wasn't overbooked, but it's not clear that that's evidently true. It's certainly gonna be contentious and probably up to a judge or jury to decide if it actually gets that far. I doubt it. The more pressing matter is what do you do as a passenger when YOU are involuntarily denied boarding due to overbooking? Are you gonna sit in place, say, "I don't believe you." and wait for the stasi to take you away for a beating?