You would have to at least poll a panel of the submitter's peers.
Actually, that is the way it's supposed to work. I don't know how often this is the case. During the internet boom, one of the biggest reasons for bogus patents IMO was that it was impossible to know who ws an expert in the field. I think this is less the case with more mature industries. Unfortunately, a few bad apples...
As I pointed out earlier, one of this biggest problems is that an idea that was non-obvious at the time of the filing, may seem like a no-brainer by the time the patent is issued. It's kinda like learning a magic trick. It seems impossible when you first see it, but once someone shows you how to do it, it couldn't be more obvious.
I agree that the legal system has largely subverted the intent of the patent process. The patent process was designed to protect the independent inventor from abuse by large corporations (this is why only individuals, not corporations, may be granted patents. Before anyone points out the obvious, yes, inventors can assign all their patent rights to a corporation, but the patent still "belongs" to the inventor). Unfortunately, the economics of filing, prosecuting and defending patent claims have made it extremely difficult for the independent inventor and much easier for the corporations to take advantage of these protections.