Nelson Hart will serve 30 days of house arrest and one year of probation for an incident at Her Majesty's Penitentiary in St. John's on Jan. 30, 2013.
The 46-year-old man was convicted in February of threatening to stab a male guard after a dispute as Hart was held in segregation.
A guard testified Hart became irate when asked to open his mouth to prove he'd swallowed his medication.
At the time, Hart's first-degree murder conviction in the 2002 drowning deaths of his three-year-old twin girls had been overturned but he was still behind bars pending an appeal.
Hart was released last summer after the Supreme Court of Canada ruled confessions he made to undercover police posing as gangsters were inadmissible. The high court said the investigative tactics potentially breached Hart's Charter rights, casting doubt on evidence gathered in similar stings across Canada.
Monday's sentence is consecutive to a 60-day sentence of house arrest Hart received last month in a separate incident of threatening jail guards.
In that case, a prison video played in court showed how a guard spilled Hart's lunch on the floor of his cell on June 24, 2013. The incident escalated and correctional officers testified that Hart had threatened to kill them.
Hart was tried in this most recent case by Judge Lois Skanes alone. Asked Monday if he had anything to say, Hart replied: "No, thank you."
Skanes agreed with the sentence proposed by Crown attorney Mike Murray.
Defence lawyer Jeff Brace agreed, but told the judge before sentencing that Hart's behaviour in jail was out of character.
"No one is trying to make excuses," he said. Still, he stressed, Hart served a total of nine years and three months and was awaiting the outcome of his ultimately successful appeal at the time of the outburst.
"Frustrations had reached an all-time high."
Brace said his client may be free but is a social outcast who has struggled to find housing and has been attacked "at least three times, once on a city bus."
"He suffered things we probably can't comprehend," Brace said of Hart's time in custody.
Former lawyers for Hart said last summer they would discuss pursuing a civil lawsuit for wrongful conviction compensation. There has been no action filed to date.
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