I wish I too knew if interfering is helpful. A youngish boy (that awkward 12-15 age group) was surrounded by a group of bicycle police right before you enter our co-op quad. I was coming home from work and it really made me uncomfortable riding past. I actually circled a couple of times before heading up to my apartment and watching out the window. Eventually a man went over and talked to the group and it seemed to sort out.. I was mostly worried I'd embarrass the kid if I asked him if he was okay. I still feel like a grade A jackass for not making sure he was okay though.