WASHINGTON, July 25 — Legislation drafted by the Bush administration setting out new rules on bringing terror detainees to trial would allow hearsay evidence to be introduced unless it was deemed “unreliable” and would permit defendants to be excluded from their own trials if necessary to protect national security, according to a copy of the proposal.

The bill, which officials said was being circulated within the administration, is not final, but it indicates the direction of the administration’s approach for dealing with a Supreme Court decision that struck down the tribunals established to try terror suspects at Guantánamo Bay, Cuba.

The 32-page bill preserves the idea of using military commissions to prosecute terror suspects and makes modest changes in their procedural rules, including several expanded protections for defendants, many of them drawn from the military’s legal code. But the proposal also sets up a possible confrontation with lawmakers who have called for modeling the trials on the military’s rules for courts-martial, which would allow defendants more rights.

The draft measure describes court-martial procedure as “not practicable in trying enemy combatants” because doing so would “require the government to share classified information” and would exclude “hearsay evidence determined to be probative and reliable.”