The federal Crown is seeking dangerous offender status for Mark Lange, a 40-year-old Yukon man with 42 convictions, including six for violent crimes.

The status could put Lange in jail indefinitely.

Alongside Dean Boucher, Lange was convicted of manslaughter in the death of a Carcross hotel owner in 2004.

Both were originally found guilty of second-degree murder. However, the Yukon Court of Appeal overturned the sentence in 2011 citing contradictory instructions the presiding judge told the jury.

On Friday, Crown prosecutor Noel Sinclair noted the crimes Lange had committed fit two of the requirements for the status: a pattern of persistent aggressive behaviour, and a failure to restrain his behaviour and a likelihood of causing death or injury to other persons.

In the case of an indeterminate sentence, it must be shown a lesser sentence would not protect the public adequately.

Sinclair pointed to Lange’s lengthy criminal record.

“There is no appreciable gaps in his criminal behaviour,” he said, referring to the 42 convictions staggered between the 1990s and 2014.

Among the violent offences he was convicted of, Lange was sentenced in the 1998 assault of his spouse.

Amidst an argument, Lange repeatedly choked her, then threw her to the ground.

The same year, Lange broke into a man’s house and beat him up, helped by accomplices, leaving the man unconscious.

In late 2004, he and Boucher beat up Carcross hotel owner Robert Olson, who died as a result of the injuries.

In the Carcross case, the evidence was unclear to qualify what role Lange had, Sinclair said.

He noted that Olson was struck 15 times, resulting in bruising and fracturing of the nose and cheeks, and lacerations to the face.

In January 2013, Lange made death threats to his spouse on Facebook.

On June 6 last year, Lange was filmed repeatedly beating up a man outside the Salvation Army.

For no apparent reason, he first punched the man, who dropped to the ground.

He walked away, then returned to kick, punch and stomp on the man’s head as he was laying on the ground. He walked away again, only to return to beat up the man.

The victim was left laying on the ground for a “considerable period of time,” Sinclair noted, before being discovered by Salvation Army staff.

Sinclair noted the “alarming display of unprovoked violence” in the beating of the man.

The prosecutor told the court he believes Lange, who was assessed by Dr. Shabehram Lohrasbe, is an intelligent man who tried to “con” the physician in his 2012 and 2015 reports.

Lohrasbe was “uncertain about (Lange’s) capacity to accept treatment and be rehabilitated while the public could be protected,” Sinclair said, reading from the report.

Lange’s intense anger has been a long-established part of his psyche’s make-up, Lohrasbe noted.

His antagonistic attitude with police officers undermines his safe management in the community, Sinclair said.

“Lange needs to have a track record of co-operation, honesty and disclosure,” said Sinclair.

While there’s a possibility Lange could be locked up for life, the prosecutor told the judge he could also be eligible for parole after four years’ imprisonment.

“I’m not asking the court to throw Mr. Lange in a black hole and throw the key away,” Sinclair said.

“I’m asking he be put in an environment where he can earn his release,” he said, adding the public had to be protected.

With a fixed sentence, Lange would be automatically out once he reached his statutory release date, even if he didn’t meet the therapeutic goals imposed by the court, Sinclair said.

Defence lawyer Gordon Coffin took issue with his client being assessed for the status.

“It is intended to capture relatively few offenders,” he said, notably those who are in the extreme end of the violent behaviour spectrum.

“Not everyone who may be a danger to the public is therefore a dangerous offender,” he said.

Coffin pointed out Lange’s role in the beating following the break and enter wasn’t clear from the evidence at trial.

He also refuted the classification of the Facebook death threats as “violent.”

Coffin asked the judge put his client on long-term supervision, instead of being declared a dangerous offender.

He also asked for a six- to seven-year prison sentence.

Coffin also noted Lange has repeatedly pleaded guilty in previous cases, showing an acceptance of responsibility.

Justice Donald Luther is scheduled to rule on the matter Nov. 25.