A prisoner, once described by a judge as a "chronic, high-level nuisance", menaced his late brother's partner from behind bars with a letter that warned hell would rain down upon her once he was released.
Matthew John Millard's latest stint in Canberra's jail began in July 2018, when he stole an elderly woman's mobility scooter and set his dog on a police officer who came to his Rivett home to question him.
The career criminal encouraged the pit bull as it mauled the constable, who was seriously injured.
When Millard faced the ACT Magistrates Court the next day, he threatened to kill police officers seated in the public gallery and pretended to shoot them with his fingers, saying "pew, pew, pew".
In relation to both incidents, he was sentenced to a jail term that does not expire until November 2023. His non-parole period was, meanwhile, due to run out in March 2022.
However, an ACT Supreme Court appeal decision, published on Monday, shows Millard's minimum jail term was extended in August after a magistrate found him guilty of using a postal service to menace.
In the decision, Associate Justice Verity McWilliam said Millard had committed the federal offence by sending a handwritten letter to the victim's home in May 2021.
The victim had been in a relationship with Millard's brother, who died by suicide, and she interpreted the one-page letter as blaming her for the death.
"I dream about how I'm going to get revenge on the woman who killed my big brother," part of the letter read.
"If it wasn't for my little niece, you would be sleeping beside him."
Millard also told the victim she had "no idea what kind of person I am and how well connected I am".
"Because of you I couldn't come to my own brother's funeral," he wrote.
"I'm giving you this one chance, and one only, to do the right thing by my brother and my niece to know me.
"If not, I'll be out in 9 months and hell is going to rain down upon you."
Special magistrate Margaret Hunter sentenced Millard over the letter to four months in jail, but she made the term wholly concurrent with the offender's existing prison sentences.
Ms Hunter set the latest term to expire on December 11, effectively extending Millard's non-parole period until that date.
Millard recently appealed against the sentence imposed by the magistrate, arguing it was manifestly excessive.
The self-represented offender, who suffered severe brain damage when he overdosed on heroin in 2012, also contended that Ms Hunter had failed to clearly articulate the discount he received because of his mental illness or impairment.
Associate Justice McWilliam ultimately found no error in either regard, and dismissed the appeal last Friday.
Her decision noted Millard was expected to front the Sentence Administration Board for a parole hearing on Tuesday, ahead of his potential release in a few weeks' time.
