Irvin Fraser, 30, from Aberdeen, was sentenced to 13 months after admitting pocketing child tax credits totalling 79,718 over three years.
The recovering heroin addict began the scheme to feed his habit, Aberdeen Sheriff Court heard. But the scam went undetected by HM Revenue and Customs – despite four claims being made for the same children.
Fraser, who has two children, admitted making the fraudulent claims in writing and over the phone between November 2003 and June 2006. The claims were made in four names and began with a claim for an extra two children. All the payments were made into one bank account.
By September 2005, he was claiming for 14 children, spiralling to 36 by the time he was questioned by HMRC investigators a year later.
The court heard Fraser admitted during an interview to signing forms his partner had completed and to making phone calls in relation to the claims. Prosecutors accepted a not guilty plea by his co-accused, Annette Fraser.
Sheriff Alexander Jessop said: "It seems surprising that you can simply phone up and children can be added … and then payments can be made into a bank account for 36 children and no checks are made." The sheriff added: "The children didn't even exist – don't you need a birth certificate or something?"
Sentencing Fraser to 13 months, he told him: "I can't ignore the fact that this was a sustained form of fraudulent activity which resulted in 79,718 being obtained by you."
Shane Campbell, Fraser's lawyer, said his client began making the fake claims after a friend told of success in getting cash. At the time, he was using 150-200 worth of heroin daily, he said.
The lawyer disputed a social inquiry report which stated that Fraser, of Aberdeen's Torry area, did not think his crime had any victims. He said: "He accepts that there were victims of this case. As a result of the considerable media coverage, Mr Fraser has had to deal with a substantial amount of ill-feeling, particularly within his own area.
"It's not surprising they are less than happy regarding his conduct … made clear to him on numerous occasions when he's felt safe to leave his home."
Anne-Marie Gordon, the HMRC assistant director of investigations in Scotland, described Fraser's actions as "a premeditated attack on the tax credits system".
She said: "Making fraudulent tax credit claims is not a victimless crime and he had little consideration for the public purse or the individuals whose identity he used to commit this fraud.
"This investigation has shown our determination to seek out people who are tempted to cheat the tax credit system."