If Mr. Hayes is tried or enters into a plea agreement in the U.S., British prosecutors wouldn't be able to try him on similar charges under U.K. double-jeopardy rules, according to criminal-defense lawyers who aren't involved in Mr. Hayes's case.

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In that case, British double-jeopardy laws likely would preclude him from being extradited to the U.S. to face similar charges, the lawyers say.

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Dianne Feinstein, D-California, argued that U.S. troops would be put in "jeopardy" if Obama does not listen to McChrystal.

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Dianne Feinstein, chairwoman of the Senate Intelligence Committee, said U.S. troops would be put in "jeopardy" if Obama does not listen to McChrystal.

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According to Science Magazine, specific science and technology-based programs in jeopardy include, National Institutes of Health, National Science Foundation, U.S. Department of Energy, NASA, and Environmental Protection Agency, to name a few.

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"Under U.S. law, she was once put in jeopardy and later acquitted, " Casey said.

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The NHL hoped to open camps on Sunday, and that prospect seemed in jeopardy Saturday until the document was signed at 10 p.m. eastern U.S. time.

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Another key aspect of the Knox case: The Italian system does not include U.S. Fifth Amendment protection against a defendant being put in double jeopardy by government prosecution.

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