Moore tells The Associated Press in an interview that he considers Pfc. Bradley Manning a courageous patriot for exposing what Moore called "war crimes."
The Oscar-winning filmmaker said Thursday he will contribute to a legal defense fund for the 22-year-old former intelligence analyst, who faces up to 52 years in prison.
Manning is charged with leaking video of a U.S. Apache helicopter attack that killed 11, including a Reuters news photographer and his driver.
Investigators call Manning a person of interest in the release of 77,000 Afghanistan war logs that WikiLeaks published online in July.
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