But at least five of the eight senators writing the bill have backed biometric ID cards in the past.

WSJ: Senators in Immigration Talks Mull IDs for All Workers

Mr. Graham, in an interview, said that in his mind the language refers to a requirement for biometric ID cards.

WSJ: Senators in Immigration Talks Mull IDs for All Workers

Biometric ID methods are being built into digital cameras, and as costs fall they will proliferate into every nook and cranny of America.

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The lawmakers haven't committed to the "biometric" ID card, and are wary of any element that might split the fragile coalition of Democrats, Republicans and outside organizations working toward agreement on a broad overhaul of immigration laws.

WSJ: Senators in Immigration Talks Mull IDs for All Workers

Biometric technology has replaced badges and ID cards for employees at many airports.

CNN: graphic

An Israeli outfit called On Track Innovations (nasdaq: OTIV - news - people ) has developed chips that carry biographical and biometric data to be inserted in ID documents.

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Last week a foreign student in Cambridge showed me his residence permit for the UK, the bit of plastic, plus biometric chip, that was to be the prototype for the ID cards that everyone was threatened with - but is now issued only to visa holders.

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This second ID could be a small piece of hardware, such as an electronic key fob, or a biometric (see the next paragraph).

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