Purdue app aims to wipe out gang graffiti

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You don't have to go far in Indianapolis to find graffiti. It may look like a jumble, but researchers at Purdue are using sophisticated techniques to help police read the writing on the wall and keep your family safe.

You can see it under bridges, on the side of buildings, even on delivery trucks moving through the streets. Graffiti is easy to find in central Indiana, a visible sign that gang members are at work in our neighborhoods. They see graffiti as a marketing tool, a sign that they exist, that they others should pay attention.

According to an undercover IMPD detective, "No matter what the gang members are doing, they're not out here for bake sales and to help grandma cross the street. Gang members, by their very nature, are criminal organizations."

The anonymous detective has been undercover for more than a decade. What gangs do has remained the same in that time.

But how they do it has changed.

The detective says the problem that used to be contained to inner-city neighborhoods, has now moved to the suburbs. Today, gangs are as close to us as Facebook and Twitter.

"As long as kids still have access to the Internet and go to school and meet with each other, it doesn't matter where your child is from, what school they go to, or what most people would consider to be normal factors," the detective says.

But if Facebook and Twitter are today's marketing tools, graffiti is like the "old media" of the gang world. Purdue University researchers are using modern methods to unlock what we can learn from it.

Purdue professor Ed Delp is working with a group of graduate students to catalogue each crude drawing. Based on what police already know, the program can draw conclusions. It can also plot the drawing in relation to others in the area. The computer puts it together, giving police information in seconds that used to take months - and shoe leather - to gather.

"This is a research project. I'm interested in working on really hard problems and this is a really hard problem," Delp said, "and in this case, we're going to be able to help law enforcement agencies throughout Indiana and hopefully throughout the U.S."

Here's how it works: Purdue offers police a cell phone application. It is free, private, and it can give police insight into the problem that they have never had before.

Police take pictures with their smartphones and upload them into the Purdue database. The more pictures in the system, the more information they get back.

"To put it all together, you can search the database and you can get some idea of how these images are distributed across the city," said Delp, "both in time and also on the map and this will give you some idea of where gang activity is occurring."

Right now, the system is operating in Indianapolis and West Lafayette, but the Purdue researchers are willing to spread the technology to other police departments in Indiana. The system works best with the most information.

The app is free and Purdue is working to get other police departments on board and in the system. Our undercover detective says the gang problem is not going away, but solving the puzzle of graffiti may be a key to making progress to control it.

"Tattoos, wearing specific clothing, hand signs, handshakes and graffiti are just baseline items that all of our gang members feel they have to do to represent their gang," the detective said.

To take a line from a popular advertisement, for the good guys in the equation, there's now "an app for that."