Prosecutor John Murphy said evidence in Salim Hamdan’s two-week trial showed the Yemeni detainee played a “vital role” in the conspiracy behind the 2001 attacks.
Hamdan was captured at a roadblock in southern Afghanistan in November 2001 with two surface-to- air missiles in the car.
Prosecutors accused Hamdan of transporting weapons for al-Qaida and evacuating bin Laden to safety after learning he was about to launch terrorist “operations” including the September 11 attacks.
Hamdan’s Pentagon-appointed attorney Navy Lt Cmdr Brian Mizer countered that the defendant was a low-level bin Laden employee who never joined the al-Qaida conspiracy against the US: “Not one witness said he had any role in the terrorist attacks themselves.
“Mr Hamdan is not an al-Qaida warrior.”
A jury of six military officers was due to begin deliberating a verdict yesterday.
Hamdan is charged with conspiracy and supporting terrorism.
He faces a maximum life sentence if convicted at the first US war crimes trial since World War II.
The judge, Navy Capt Keith Allred, said at least four jury members must find Hamdan guilty “beyond a reasonable doubt” to convict him.
Allred reminded jurors he allowed evidence from FBI interrogators who did not advise Hamdan of his right against self-incrimination and urged them to decide its merit for themselves.
“You must decide the weight and significance, if any, such statements deserve,” he told the jurors.
Hamdan is one of roughly 80 prisoners that the Pentagon plans to prosecute in the tribunal system.