POSTED: Tuesday, May 13, 2008 -- 3:45pm

A convenience store on Madison's northeast side takes a unique approach to prevent thefts at the pump.

The Citgo on Commercial Avenue has what it calls, the window of shame.

It includes the pictures of people who fill up their tanks and drive away, without paying.

The pictures are printed from surveillance video.

Right now, there are 26 photos on display. One shows a man who allegedly owes $85.

The store manager says these are the most recent drive-off cases. The latest happened back on Sunday.

Nowadays, several gas stations require people to prepay before they can fill up, to avoid theft.

However, store manager Kendra Schlittler says she likes to give customers the benefit of the doubt.

"It would be a hassle to our customers and our customers would go somewhere else, that would not have the mandatory prepay," says Schlittler.

She says it takes around two days to make up for just $20 of stolen gas.

The window of shame has been around for about three years. Since then, around 500 photos have come and gone.

In one instance, Schlittler says a mother noticed her son in a picture and paid off his debt.

Madison police call gas theft a preventable crime. Spokesman Joel DeSpain tells NBC 15 it's not a trend the department regularly tracks.

Nationwide, gas thefts totaled $134-million in 2007. That's about $1,000 per station, according to the National Association of Convenience Stores.