Christopher Edward Newhook being escorted out of the courtroom on Tuesday. (CBC)

A sentencing hearing for a man charged with aggravated assault took a startling turn on Tuesday when the man began to shout at the Crown attorney during closing arguments.

Prosecutor Catherine Cogswell is trying to have Christopher Edward Newhook declared a dangerous offender for stabbing a man in the forehead in Halifax in 2007.

"He indicated that he wished he could 'effing cut my head off with a rusty hack saw,'" Cogswell said outside the courtroom. "At that point he became more aggressive and made references to my mother … and looking right at me as he was hollering the threats."

She called the Halifax police, who sent an officer to the courthouse. Extra sheriffs where also called in for the remainder of Newhook's court appearance

Cogswell said she should not have had to put up with Newhook's outburst.

"I felt scared and intimidated, but at the same time, I wasn't going to back down from my legal position which I needed to put forward," she said.

Newhook, who is 40, has approximately 50 previous criminal convictions and has spent about half his life behind bars. He has committed many of his crimes against visible minorities.

In court, the Crown argued that the evidence showed Newhook is a psychopath and a racist who must be declared a dangerous offender and be locked away indefinitely for the safety of the public.

"I think that's what set him off," said Cogswell. "He can't even control himself in this application."

Defence lawyer Jean Morris said she wanted Newhook declared a long-term offender, which means a set time in prison followed by 10 years of supervision in the community.

Justice Bill Digby will present his decision on the dangerous offender application on March 1.