Brian Francis Maloney had his client act as a lender to third parties for five years, only to use the money to address his own financial difficulties, the Supreme Court heard on Friday.

Maloney never sought the permission of the third parties but included their details in falsified documents given to the victim, Chief Crown prosecutor Gavin Silbert, QC, told the court.

Mr Silbert said Maloney had paid back almost $1.1 million of the money he defrauded between January 2007 and February 2012, but that the victim had lost more than $650,000.

Maloney, 59, a one-time legal clerk who worked for what became the Office of Public Prosecutions and who became a successful lawyer in his own right, pleaded guilty to 13 counts of obtaining property by deception.

The father of six sons sat with his head bowed in the dock for much of his plea hearing as defence counsel Ian Hill, QC, outlined his client's struggles with depression and financial problems.

Mr Hill said Maloney, who had owned his legal practice, had reflected on his 50th birthday how lucky he was, but that "sadly, things would change and would change fairly quickly".

Maloney defrauded his client to try to get himself out of debt, the court heard, and at the start of last year planned to kill himself so a life insurance payout would cover his debts and repay his victim.

Mr Hill said Maloney wanted to make his death look accidental so he planned a car crash on a rural road. But by chance one of his sons was in the area and came across his father before his suicide attempt, and he began treatment for his mental-health problems.

The court heard Maloney's depression could be traced to his mother's death in 2003 and that he ran into financial troubles when he undertook pro bono legal work for a friend and his wife's clothing business struggled.

Maloney estimated the pro bono work he performed for his friend – which involved a civil case and two subsequent appeals – cost his business about $2 million, Mr Hill said.

The court heard Maloney was a decent man of good character who volunteered for his local football club to spend time with his sons, and who was remorseful and apologetic.

"This is not a case where the prisoner was accustomed to the high life, an extravagant lifestyle, gambling or the consumption of alcohol," Mr Hill said. "This was a man who ... had two things in his life, his work and his family.

"There were bad decisions made, financial, and it is with the greatest shame and embarrassment that he stands here having betrayed the profession he held dearly. It has always been his desire, and continues to be, to repay [the victim]."

Mr Hill told Chief Justice Marilyn Warren a prison term would be onerous given Maloney's depression. But Mr Silbert said similar cases of lawyers defrauding clients had attracted prison terms and that jail was warranted.

Maloney, who also pleaded guilty to two counts of having a deficiency in a trust account and one count of theft, was remanded to be sentenced at a later date.

For help or information visit beyondblue.org.au, call Suicide Helpline Victoria on 1300 651 251, or Lifeline on 131 114.