Do they honestly think the Beltway Sniper would voluntarily turn over a weapon used in at least ten murders just because they asked for it?
Conversely, do they honestly think they can track down and test every .223 caliber firearm in the area except the Beltway Sniper's and thus isolate him that way? Will the Beltway Sniper be the only recorded owner of a .223 rifle that can't be located or questioned? Who's to say the "sniper" doesn't normally live somewhere else far, far away, and went to the D.C. area specifically to commit these crimes? In any of these cases, searches of local records are worthless, whether the gun was bought locally or not.
There is no logical case in which the random search scenario makes sense -- at least from a legitimate law enforcement standpoint.
The only conclusion I can come to about these questionable searches and seizures, having read about it from multiple sources, is that it is some strange reactionary combination of opportunistic power politics, morbid grandstanding, blind panic and unadulterated lunacy that is being undertaken without regard for legality, morality or reality.
Oh, and that this makes an airtight case against any form of gun registration at any level of government. Even without legitimate authority, massive abuses of this presumptuous power are already taking place.
I, for one, will never cooperate with any activity that violates constitutional law. I'm sworn to protect the U.S. Constitution, and will not renounce my oath for anyone or any reason. Those who would usurp powers that are not rightfully granted to them do so at their peril.
Molon labe.