so how do they catch him? no fingerprints at the scene, no dna evidence. if there's fingerprints on the bike, there's also the prints of hundreds of other people.  they need video of his face, and they need it before he changed. even if he drops his gun and they get his prints, they need his prints to already be in the system, or the gun registered to his name.  if it's a stolen or otherwise unregistered gun, and this guy now drops the gun in a sewer and donates his clothes to a thrift store, is there any conceivable way to find him, much less convict?
Canada