Behead threats 'blown out of proportion'

A Sydney man who allegedly claimed he was a member of Islamic State before threatening to behead a police officer says the whole thing has been "blown out of proportion".

Lamin Savage, 24, is accused of calling Granville police station in Sydney's west in September and threatening to cut off the head of an officer who had arrested him for driving offences two months earlier.

Police say Savage claimed to be a member of the Islamic State when he made the call.

But on Wednesday the 24-year-old interrupted his bail application and told the Supreme Court that "things have been blown out of proportion".

"I just made a phone call to the cop shop to make a complaint," Savage said while appearing via audio visual link in prison greens.

"It is just distressing. I don't want my family drawn in on this."

The refugee from Sierra Leone made the comments after his mother Bintu Savage gave evidence that she could supervise her son if he was released on bail and could post the $400 as surety.

The court heard Savage had been diagnosed with a borderline intellectual disability.

Although the crown consented to him being released on bail, Justice Helen Wilson said it was a "very serious offence".

She will hand down her decision at a later date.

In denying him bail at Parramatta Local a court earlier this year, Magistrate Margaret McGlynn said the facts before the court were "of great concern".

"The latest charges fit info a disturbing pattern of escalating threats," Ms McGlynn said in September.

Savage, who has been charged with using a carriage service to threaten to kill and three driving offences, is expected to face a local court hearing in March.