Bennie Dean Herring was "no stranger to law enforcement," according to Chief Justice of the United States John Roberts. That's Roberts' understated way of saying that when Herring walks into a room, reasonable people could be forgiven for hearing the theme music to "Cops" in their heads.

Herring visited the Coffee County, Ala., sheriff's department on July 7, 2004, to get something from his truck, which had been impounded. Mark Anderson, an investigator with the department, asked the county clerk if Herring had any outstanding warrants.

Some might say that when a law enforcement officer's first reaction upon laying eyes on you is to check for outstanding warrants, you've made some poor life choices.

Anyway, the clerk said no. Then Anderson asked if there were any warrants from the next county over. Voila, the clerk found one for Herring's failure to make a court appearance. Anderson and a deputy proceeded to arrest Herring and search him and his vehicle. They found a gun (which was illegal thanks to a previous felony conviction) in his truck and methamphetamine in his pocket.

Then the clerk said, in effect, whoops! That's an old warrant and it shouldn't have been in the computer any longer.

Herring and his lawyers argued that his arrest and subsequent conviction were unconstitutional since law enforcement didn't have probable cause to conduct a search. The Supreme Court, in a 5-4 decision, disagreed this week. Legal observers are debating whether Herring v. United States is a landmark curtailment of the exclusionary rule or a small technical correction. Alas, out of concern for the status of my eternal soul, I refrained from becoming a lawyer, so I'll let others hash out that question.

Meanwhile, some of my libertarian friends are vexed by this. Glenn Reynolds (the 800-pound gorilla blogger known as Instapundit) writes in the New York Post that police shouldn't be exempt from following the law like everyone else. Reynolds understands the court's reasoning: "Why punish the police by letting a guilty man go free when they just made a simple mistake?" But, he reasons, ignorance is no excuse for John Q. Public, so why should it be one for Johnny Law? "Being a 'public servant,' apparently, means being free to make the kind of mistakes that the rest of us aren't allowed," writes Reynolds.

I've never understood this argument.

Now, I agree that cops should follow the law just like everyone else. I just don't understand how Reynolds and so many others get from there to the idea that punishing cops requires rewarding people like Herring. According to the exclusionary rule, a cop who breaks the rules to arrest a serial child rapist should be "punished" by having the rapist released back into the general public. (Or as Benjamin Cordozo put it in 1926 when he was a New York state judge, "The criminal is to go free because the constable has blundered.")

But the officer, while frustrated, isn't really punished. The people punished are the subsequent victims and their families.

Reynolds and others say police should be subject to the same laws as other citizens and public servants. I agree. But if a husband runs a red light to get his pregnant wife to the hospital, she's not turned away because he broke the law. Or, imagine if a health inspector had the wrong address on his paperwork and rummaged around the wrong restaurant, only to find a roach and vermin infestation the likes of which are rarely seen outside of an Indiana Jones movie. According to the logic of the exclusionary rule, the public should keep eating roach burgers and rat droppings because the eatery was illegitimately searched. That's cuckoo for cocoa puffs.

One answer -- really the only answer -- you hear about why we should treat criminals with more respect is that it's the only way to make government respect the rights of the innocent. I'm all for respecting the rights of the innocent, and I think police should be required to follow strict rules, have warrants and all the rest. But I don't see why cops who break the rules intentionally or unintentionally should be "punished" by having objectively guilty criminals let loose on society. I don't think zookeepers should abuse their animals, but nor do I think a zookeeper's abused polar bear should be set free in Midtown Manhattan. If Special Forces troops break the rules while capturing Osama bin Laden, I don't see why that should require letting bin Laden go and giving him a do-over.

If zookeepers, soldiers or cops break the rules, punish them -- criminally, civilly or administratively. But don't reward the scum of the earth with a get-out-of-jail-free card, particularly when that will result in truly innocent people being punished. Criminals didn't do anything right just because the cops did something wrong.