One night last summer Raymond Bell was pulled over by a Chicago cop and arrested for driving under the influence. Officer Joe D. Parker, a 23-year veteran, reported that upon getting out of his car, Bell was stinking of alcohol, lurching and unable to walk a straight line or stand on one foot.

An officer with his stellar record would normally prevail against a DUI suspect. But in this case, Bell had something on his side: a video camera mounted on the dashboard of Parker's squad car that told a radically different story.

Far from revealing a staggering drunk, reported the Chicago Sun-Times, the video "showed Bell appearing to be perfectly balanced," passing the sobriety tests that Parker administered -- and being refused when he asked to take a Breathalyzer. Prosecutors watched the video and promptly dismissed the case. They are now considering charges against Parker.

That episode raises the question: Nine years into the 21st century, why isn't every squad car in America equipped with a dashboard video camera? Why do we persist in relying on the slippery, self-interested, incomplete and unverified accounts of opposing participants when we have the means to see the truth with our own eyes?

In this instance, the innocent man was lucky to be stopped by a cop driving a video-armed vehicle. The odds are against it, since only 11 percent of the CPD's cars have cameras for recording traffic stops. Though the department is planning to use federal stimulus money to double that number and the mayor has said he wants cameras installed in the remaining vehicles "as quickly as possible," no one is radiating a sense of haste.

Why not? The department says the main obstacle is money. Equipping another 300 cars, as the city plans, will require $2.1 million. So making them standard on the rest would cost about $13 million.

But that shouldn't be an insurmountable obstacle. The Illinois State Police, with a fleet of nearly 1,100 vehicles, have managed to install cameras in more than 900.

Spending $13 million looks extravagant only until you compare it to the cost of losing lawsuits over police misconduct. From 2005 through the middle of 2008, says the Chicago Reader, the city paid out $155 million in police cases. Dashboard cameras don't have to prevent many million-dollar judgments to be a bargain.

The cops -- at least the good ones, who are presumably the majority -- have as much reason to want these recordings as the accused. The best defense against a phony charge of police brutality is a video showing exactly what the officer said and did. A suspect who is visibly inebriated or violent will have a hard time refuting the camera's testimony in court.

Yet Chicago has dragged its feet, and it's not alone. After the 1991 Rodney King beating, a commission recommended that the Los Angeles Police Department mount cameras in its squad cars. It installed some but soon got rid of them.

A federal monitor proposed the idea again in 2005, but the police chief, The Los Angeles Times reported, "said he saw it as a long-term project." Last year -- 17 years later -- the LAPD finally decided to equip some vehicles.

Contrast that with Chicago Mayor Richard Daley's enthusiasm for other types of video. Chicago now has some 2,250 surveillance cameras to detect criminal conduct in public places. By 2016, Daley promised last month, Chicago will have one on every corner. The city has also installed red-light cameras at some 132 intersections, with another 330 planned.

So what exactly is different about those cameras? Well, they are trained on the citizenry, not on the police. What's sauce for the goose seems to be regarded as a dubious liquid substance when proposed for the gander. The city is less eager to capture video evidence if it may expose wrongdoing by its own law enforcement agents.

But the rest of us might want to keep unsleeping electronic eyes on the people with guns and badges. A city with a good police department can gain a lot from squad-car video cameras. A city with a bad one can gain even more.