If I approach as you pull into a parking space and ask if you'd mind my rummaging through your car, the chances are at least 90 percent that you'd decline. But if a police officer stops you with the same request, the chances are higher than 90 percent that you'd agree. Something about that badge makes citizens eager to be helpful.

Or maybe not. In civics class and Fourth of July speeches, we are told that American democracy rests on the consent of the governed. But interactions with the police serve as a useful reminder that government rests less on voluntary cooperation than on fear and force. A nation is free to the extent it prevents the rulers from bullying and coercing the ruled. By that standard, American society still has a way to go.

The other day, the American Civil Liberties Union of Illinois issued a report on "consent searches" that sometimes accompany traffic stops. Relying on data provided by local and state law enforcement agencies, the report documented that black and Hispanic drivers are much more likely than whites to suffer such invasions — even though the cars of minorities are far less likely to yield contraband.

These treasure hunts are called "consent searches" because they require the motorist to give permission. They take place only when the police officer has no grounds for suspicion. If he has probable cause, he doesn't have to ask. Only when he's acting out of a vague hunch, racial prejudice or simple malice does he need the driver's consent.

But the term is fantastical in these instances. Stopped on a lonesome stretch of highway, at the mercy of an armed man who has the power to arrest, very few citizens feel free to refuse. The Illinois State Police report that 94 percent of white motorists and 96 percent of minority ones "consent" to such searches.

Is that because they have nowhere else they'd rather be? Is it because they get a kick from watching a cop take apart their cars in an effort to put them behind bars? Or could it be because they suspect that refusing a cop is far too dangerous?

More than 40 years ago, the Supreme Court ruled that before interrogating a suspect in custody, police have to provide the now-familiar warning: You have the right to remain silent; you have the right to an attorney; anything you say may be used against you.

Said the court, "The atmosphere and environment of incommunicado interrogation as it exists today is inherently intimidating and works to undermine the privilege against self-incrimination." Only a firm safeguard, in the form of the magic words, could "dispel the compulsion inherent" in these situations.

The same inherent compulsion exists in traffic stops, but the court declined to follow its own logic. So the Fourth Amendment ban on unreasonable searches is virtually meaningless on the roadside.

But the court's myopia is no reason a state can't abandon this obvious abuse on its own. As it happens, "consent" searches are a fool's errand. Fully 94 percent of the time, the Illinois State Police discover nothing illegal — meaning they inconvenience and humiliate 16 innocent people for every guilty one they turn up.

Nor is the Land of Lincoln unique. When the Texas legislature took up a bill limiting such searches, the Texas Municipal Police Association admitted that "the vast majority of the time, we found nothing."

Other states have found that effective law enforcement doesn't demand hassling citizens who have done nothing to justify suspicion. In 2002, New Jersey's state Supreme Court recognized the obvious: "These searches are not voluntary because people feel compelled to assent" and concluded that consent "that is the product of official intimidation or harassment is not consent at all."

It ruled that police may not search a car without "an articulable suspicion that the search will yield evidence of illegal activity." The following year, the Minnesota Supreme Court followed suit. Rhode Island banned them by statute in 2004.

As the ACLU argues, that is the only sensible solution. In Illinois, the burden of these searches falls disproportionately on racial minorities, but achieving perfect racial equity would not alter their oppressive nature.

In a nation founded on respect for the rights of every person, these searches give all priority to the power and convenience of the government, while mocking the liberties we are supposed to have. Why would we consent to that?

Steve Chapman blogs daily at newsblogs.chicagotribune.com/steve_chapman. To find out more about Steve Chapman, and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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