Man refused bail over beheading threat

A Sydney man who allegedly claimed he was a member of Islamic State while threatening to behead a police officer has been denied bail in the Supreme Court.

Justice Helen Wilson said on Thursday that there was a significant risk Lamin Savage would reoffend if released from custody, as he appeared to have difficultly controlling his "hot-headedness".

Police say Savage called Granville police station in September to talk to an officer who had booked him months earlier for driving while disqualified.

Calling himself Mickey, the 24-year-old asked to speak to the senior constable before allegedly telling the cop who answered the call: "Tell him if I see him again I'm going to cut his f***ing head off."

He is then accused of calling back and saying "I'm a member of ISIS next time I see (him) I will behead the mother-f***er".

During the course of his application on Wednesday, Savage repeatedly interrupted the proceedings saying that the "whole thing had been blown out of proportion".

"I just made a phone call to the cop shop to make a complaint," he told the court.

But Justice Wilson said the call must have carried with it "considerable alarm".

Savage, she said, appears to have been "angered" by the officer who, by all accounts had done nothing more than his duty.

The court heard Savage was on a good behaviour bond over similar offences at the time of the alleged calls and had been diagnosed with a borderline intellectual disability.

He has been charged with using a carriage service to threaten to kill and three driving offences.

Savage is expected to face a local court hearing in March.