Jury retires in 'terror conspirator' case

A jury has begun deliberating at the Sydney trial of Mustafa Dirani, who's accused of acting as the "lookout" when two men exchanged a gun later used to kill NSW Police accountant Curtis Cheng.

Dirani, 24, has pleaded not guilty to conspiring with others to do prepare a terrorist act in 2015 between early August and October 2 - the day Mr Cheng was shot and killed by 15-year-old Farhad Jabar in Parramatta.

The jury retired to consider its verdict on Tuesday afternoon almost eight weeks after the NSW Supreme Court trial began.

They will also consider Dirani's backup charge of knowingly taking part in the supply of a firearm to an unauthorised person.

When the trial began on June 7, crown prosecutor Paul McGuire SC alleged Dirani was the "counter-surveillance man" for meetings between Raban Alou and firearm supplier Talal Alameddine.

He told the jury they "might well infer" one of these "highly illegal" events included the exchange of a .38 calibre Smith & Wesson revolver later passed by Alou to Jabar.

Defence barrister Mark Tedeschi QC argued Dirani was not a party to any illegal conspiracy and "knew nothing" of a telephone call his friend Alou received from Alameddine hours before Mr Cheng's murder.

Dirani at that stage was not a party to anything "other than going to have lunch together" at McDonald's, he said.