LOS ANGELES, Kalifornia - September 28, 2008 - Fingering criminals has never been so easy for Los Angeles Police Department officers.

Thanks to a new fingerprint reader the size of a cell phone, police officers that think suspects are lying about their identities can quickly check who they are and whether they have warrants out for their arrests.

The new technology - called BlueChecks - could result in more arrests not only on warrants, but also on charges of giving false information to officers.

"I've never seen policemen be so happy about something, because it really works," said Lt. Anita McKeown, who handles BlueChecks for the Los Angeles Police Department. "It makes our job a lot easier; it's an instant lie-detector test."

In addition to the LAPD, the Los Angeles County Sheriff's Department is among other law-enforcement agencies adopting BlueChecks.

The portable fingerprint reader uses Bluetooth technology to beam people's prints over the Internet and check them against a county database. A couple of minutes later, officers could get a detailed portrait of who's before them.

And with 1,000 more BlueChecks devices to be distributed by February, officers are excited.

"Everybody loves them. Everybody wants them," said sheriff's Lt. Leo Norton, who oversees the devices' distribution. "I couldn't keep them all on the shelf if I had them. They are an extremely popular and well-used tool."

When confronted with a shady character who has no ID and gives a potentially fake name, police used to have to ask a series of questions, hope to hear the truth, then let the person go. It's impossible to say how many times officers ran into wanted felons without even knowing it.

The fingerprint scanner is among the latest high-tech upgrades for crime-fighters.

Over the past few years, several LAPD patrol cars have been outfitted with license-plate scanners - cameras that "look" around and read nearby license plates to check whether any of the vehicles was stolen.