(AP) -- The American Civil Liberties Union says the U.S. Attorney's Office for New Jersey under Christopher Christie, now a GOP gubernatorial candidate, tracked the whereabouts of citizens through their cell phones without warrants.

The ACLU says the practice is disclosed in documents released Thursday by the U.S. Justice Department in an ongoing lawsuit over tracking.

ACLU lawyer Catherine Crump argues that government tracking without a search warrant showing probable cause is a violation of the Constitution. Government prosecutors argue that only a court order showing the tracking information is relevant to a criminal investigation is needed.

Christie, the Republican front-runner in the race for New Jersey governor, says he can't comment while the case is in the courts.

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On the Net: http://www.aclu.org

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