SAN JUAN, Puerto Rico - The United States filed charges yesterday of conspiracy and providing support for terrorism against a Guantanamo Bay detainee accused of having worked as a driver and bodyguard for Osama bin Laden.

Salim Ahmed Hamdan of Yemen is the third Guantanamo detainee to be charged under new rules signed last year by President Bush after the Supreme Court rejected the previous system.

Hamdan has been at Guantanamo since May 2002. It was his legal challenge that forced the administration and Congress to draft new rules for the military trials, or commissions, for the men held at the Guantanamo detention center in eastern Cuba. He is expected to be arraigned in early June, when he can enter a plea to the charges.

In the charging documents, the military said Hamdan conspired with bin Laden and other al-Qaeda leaders in the 1998 bombings of the U.S. Embassies in Kenya and Tanzania, the 2000 attack on the USS Cole, and the Sept. 11, 2001, attacks on the World Trade Center and Pentagon.

The United States contends that in addition to working as bin Laden's driver and bodyguard, Hamdan transported and delivered weapons to al-Qaeda and its associates and trained at terrorist camps.

He could get life in prison if convicted of either charge.

Hamdan's lawyer, Navy Lt. Cmdr. Charles Swift, says his client admits working as a driver for bin Laden - one of about eight men with similar duties - but denies any significant role in attacks against the United States.

A Pentagon spokesman, Navy Cmdr. Jeffrey Gordon, disputed the assertion that Hamdan was just a low-level player.

Hamdan's lawyers are seeking to have the case dismissed. "The government has decided to charge him with a series of ex-post-facto crimes," Swift said. "You can't write the law after the fact."

The United States says it plans to file charges against 80 or so detainees at Guantanamo, where it now holds about 380 men.

In a separate development yesterday, the Navy announced that Lt. Cmdr. Matthew M. Diaz, a Navy lawyer who was stationed at Guantanamo for six months, would go on trial next week on charges of passing classified information about Guantanamo detainees to an unauthorized person. The Navy has declined the identify the recipient.

Diaz, 41, of Topeka, Kan., could face more than 36 years in prison if convicted during the general court-martial due to start Monday in Norfolk, Va.

Also yesterday, the leaders of the Sept. 11 commission said a White House privacy board was not protecting civil liberties because it refused to investigate allegations of illegal detention at Guantanamo.

"We urge they revisit the definition of their mission to include issues relating to the treatment of detainees," former Rep. Lee Hamilton (D., Ind.) said in a telephone interview. He and former New Jersey Gov. Tom Kean sent the board a letter this week outlining their concerns.

Mark Robbins, the board's executive director, said board members had received the letter and would respond.