Fingerprint scanners deployed along our borders haven't caught any terrorists yet, but the FBI's Integrated Automated Fingerprint Identification System (IAFIS) has managed to catch 33,000 criminals -- including over 100 murderers and 200 sex offenders -- since it went live in September.

Some criminals and illegal aliens are even mutilating their fingertips in attempts to avoid being identified.

Reuters

"It has not only enhanced their ability to detect immigration offenses but also to apprehend suspects wanted for serious crimes such as homicide, kidnapping and sex offenses," spokesman Mario Villarreal of the U.S. Bureau of Customs and Border Protection said in a telephone interview.

The U.S. Department of Homeland Security began cross-referencing the FBI's Integrated Automated Fingerprint Identification System, or IAFIS, to help secure the United States from terrorist attack.

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Rank-and-file Border Patrol agents like the technology, which is used at border crossings and by agents who pick up illegal migrants in the desert.

"You have a guy who looks like a harmless grandfather, but lo and behold, when you run his prints through IAFIS it turns out that he's a three-times-convicted child molester from Fresno," said Steve McPartland, a Border Patrol spokesman in San Diego, Calif.

"It's the best thing that's happened to us, as it's closed a loophole that in the past allowed potential criminal aliens to be released from our custody," he added.

Unfortunately they don't consider border hoppers criminals and in many instances illegals aliens are simply caught and released with an immigration court date that less than 30% actually show up for. This creates an even more wasteful system of having to track them down or allowing a potential terrorist to remain in country.