The U.S. government has began outlining its extradition case against Julian Assange in a London court.

The U.S. argues that the WikiLeaks founder is not a free-speech champion but an “ordinary” criminal who put many lives at risk with his secret-spilling.

Supporters of Assange gathered Monday outside the high-security courthouse. American authorities want to try Assange on espionage charges that carry a maximum sentence of 175 years in prison. They say he conspired with army intelligence analyst Chelsea Manning to hack into a Pentagon computer and release secret files about the wars in Iraq and Afghanistan. Assange has been indicted on 18 charges. 

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The Associated Press reports that James Lewis, the lawyer representing the U.S. government, called the 2010 document leak "one of the largest compromises of classified information in the history of the United States."

"Reporting or journalism is not an excuse for criminal activities or a license to break ordinary crime laws," he added. 

A final decision on extradition is not expected for months or even years.