As more crimes are committed online, or with the help of online data, police departments are banding together to share tech tips and catch wrongdoing wherever it occurs.

There are times when the invasion of privacy is a good thing -- like when you're fighting bad guys. After all, criminals have also benefited from all of those new technologies that we enjoy, using digital tools for everything from defrauding credit cards to powering traditional gambling rings.

But law enforcement officials like Sergeant James Welsh have taken advantage of a host of software products to help uncover these crimes. "You and I have migrated parts of our lives to the address book, criminals are no different," he says.

Welsh, 42, works with the Westchester County Department of Public Safety in Hawthorne, New York. As a member of the forensic investigations unit, he analyzes computers, laptops, smartphones, memory cards from cameras, and any other type of digital storage unit you can think of. It's a hot area. When he arrived seven years ago, he worked alone -- part-time. Today he manages two other full-timers and a part-timer. More