And now, the mission of the Department of Homeland Security begins to creep:

The agency created to combat terrorism now is targeting those who prey on children.

Homeland Security Department Secretary Tom Ridge announced ''Operation Predator'' on Wednesday. The initiative seeks to crack down on crimes by child predators by pulling together once-fragmented investigative and intelligence resources.

It will target illegal aliens and foreign nationals who have avoided deportation.

Now, I haven't got much to say in favor of child molestors. But even pursuit of heinous criminals can run off the rails, as we in Boston have seen over and over, courtesy of our local FBI branch, whose investigation of local organized crime figures led it to tip off one homicidal informant to his impending arrest, and set up an innocent man to serve 30 years in jail for a murder committed by yet another informant.

Which is why we have checks on government authority -- checks which are notably weaker for the DHS, due supposedly to its particularly urgent mission. Bad enough, if it stays limited to investigation of real terrorists. Far worse if folks like the DHS cop I saw in the subway the other day (strictly speaking, TSA -- his uniform had "TSA" all over, including the back of the collar) start poking their noses into general law enforcement.

via Eschaton.