A former CIA contractor broke both agency rules and the law when he used a 2-foot-long metal flashlight to beat an Afghani man who later died, a prosecutor told a jury Monday in the trial of the first U.S. civilian charged with mistreating a detainee during the wars in Iraq and Afghanistan.

Lawyers for David Passaro said the former Special Forces medic was a frustrated but concerned interrogator who never hit Abdul Wali and checked daily on his condition.

"Dave is guilty only of trying to serve his country," Joe Gilbert, Passaro's public defender, said during opening arguments. "He's not guilty."

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Passaro is charged with two counts of assault with a dangerous weapon and two counts of assault resulting in serious injury. Although Wali died in his cell, Passaro is not charged in his death. If convicted, the 40-year-old from Lillington will face up to 40 years in prison.

Prosecutors said at least three paratroopers from the Army's 82nd Airborne Division watched Passaro, working under contract to the CIA, beat Wali during two days of questioning in June 2003 about rocket attacks on a remote base housing U.S. and Afghan troops.

Assistant U.S. Attorney Pat Sullivan said Passaro told the soldiers they couldn't touch Wali, but that he could, "because I have special rules."

"David Passaro had no special rules," Sullivan said. "He made them up."

Sullivan said Wali was chained to the floor and wall of a cell as Passaro kicked him, and struck him with the flashlight and his fists. Once, he said, Passaro kicked Wali in the groin, lining up like a place-kicker in football. Passaro's fingerprints were in batteries from the flashlight, Sullivan said, adding that photos will detail the extent of Wali's injuries.

Gilbert told the jury that Passaro's sole interest was in stopping the rocket attacks on the base, and once Wali surrendered, the rocket attacks stopped. On the day Wali died, Gilbert said, Passaro gave him mouth-to-mouth resuscitation while other medics tried to help.

The opening statements came after U.S. District Judge Terrence Boyle ruled the defense could not subpoena former CIA Director George Tenet, former agency operations chief J. Cofer Black, and University of California law professor John Yoo, along with several others whose identities were not disclosed.

Black is the State Department's former coordinator for counterterrorism. Yoo is an ex-Justice Department lawyer who helped write internal memos in 2002 designed to give the government more leeway in aggressive questioning of terror suspects.

Boyle said he would allow Passaro's attorneys to subpoena six witnesses whose identities are classified, and promised to rule later on four others. The judge considered the prosecutors' request to keep the officials from testifying behind closed doors before the jury was selected.

Passaro's attorneys have said they want to call Tenet and Attorney General Alberto Gonzales, formerly the White House counsel, as part of a "public authority defense" — namely, that Passaro was following orders. It was not immediately clear whether Gonzales was among those Boyle said could not be subpoenaed.

Boyle has previously limited the defense's access to several classified documents and e-mails, including a memo from the Justice Department to the CIA that Passaro contends described the kind of interrogation techniques allowed by U.S. law.

The government is prosecuting Passaro under a provision of the USA Patriot Act that allows charges against U.S. nationals for crimes committed on land or facilities designated for use by the U.S. government.

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