I worked for some years as a fingerprint technician for the police in Columbus, Ohio before finding a new career in mainframes. The hot thing back when I was in law enforcement was a brand new AFIS (Automated Fingerprint Identification System). This wasn't as glamorous as it sounds. It was a digital imaging system that would take pictures of fingerprints. The operator would then view the picture on a screen and manually place markers to indicate details (such as a bifurcation or ending ridge lines).
When the computer would look for a match, it would ignore the digital picture completely and just compare patterns of markers that it had in it's data base. It would alert the operator to the best matches it had, and then it would be up to the human to dig up the cards from out of filing cabinets and compare the prints using a magnifying glass. Just like it's been done for 100 years.
This isn't to say that AFIS machines aren't useful. They can search a database of millions of individual fingers and indicate possible matches in a few minutes. This can vastly speed up the matching of latent prints (prints found at a crime scene). They streamline the processing of suspects, which means that fewer wanted criminals will slip through the cracks. All of this is a good thing. But it's been my experience that the machines can't do it all by themselves. People trained in fingerprint ID will still be necessary, particularly if only one finger instead of all ten are used as a basis of comparison.
When I first heard that they were going to install AFIS machines in airports to check for terrorists I thought that it was amazing how far the technology had matured in just a few years. Now I realize that all of the hype is just enthusiasm and PR designed to sell the systems. Even if they can't do what they claim.
That, unfortunately, sums up most of the "homeland security" initiatives, as far as I can tell. I hope that things are better than they look.