The New York Times > Technology > Identity Badge Worn Under Skin Approved for Use in Health Care:

Real privacy concerns have emerged. “At the point you place the chip beneath the skin, you’re saying you will not have the ability to remove the ID tracking device,” said Marc Rotenberg, executive director of the Electronic Privacy Information Center, a public interest advocacy group in Washington. “I think, increasingly, if this takes off – and it’s still not clear that it will – the real social debate begins around prisoners and parolees, and perhaps even visitors to the U.S. That’s where the interest in being able to identify and track people is.”

Indeed, the debate over civil liberties and privacy has made discussing any practical benefits of a technology like VeriChip harder.

“The fact that we’re engaged in such a deep, fundamental privacy debate really does complicate the prospect for this kind of technology,” said Clyde Wayne Crews Jr., director of technology studies at the Competitive Enterprise Institute, a regulatory research group in Washington. “We haven’t even sorted out the appropriateness of a RFID tag that goes on a pallet of tomatoes,” Mr. Crews said, “much less one that can go under a person’s skin.”