Well, he's accused of hiding his face from surveillance cameras by holding his bike helmet up to his face and looking through the ventilation holes. You don't do that if you don't think it's a big deal, no?
A bicycle helmet? I might hold a helmet over my face if I were joking around or playing a prank. If I were serious (though I highly doubt I'll end up in such a situation), I would be using something other than a bicycle helmet.