A Dunedin tech expert used a piece of "malicious" computer code which caused his estranged business partner losses of $120,000, a court has heard.
Robert Ritchie Marshall (66) and Douglas McLean joined forces in 2007 to develop a software programme that would trade in foreign exchange with a view to marketing it and sharing in the profits.
They called themselves: "the founding members of the Pork Bellies Fun Club", according to court documents.
Marshall was in charge of the programming while his Hastings-based colleague boasted experience in trading.
The agreement the men signed stated Marshall would make the program — known as "Prosper" — available to Mr McLean, including its source code, as work progressed.
But by 2011, their partnership soured.
"Essentially the defendant resented being treated like an employee and believed that McLean was going to replace him once he had finished writing the programs," the Dunedin District Court heard this week.
Marshall believed he was being underpaid for what began as a part-time job but progressed to a full-time commitment as his collaborator put pressure on him to deliver.
By March 2012, the business relationship was irrecoverable.
Marshall gave three months’ notice that he would terminate the joint venture contract and withheld the latest updates to his coding.
He offered to give Mr McLean what he wanted for $120,000.
When that was declined and mediation failed, Mr McLean took his grievance to court.
In 2014, the High Court awarded him damages of almost $18,000 but declined a separate claim for $103,000.
Mr McLean said that sum was a direct result of Marshall failing to provide the source code for Prosper.
After successfully challenging that judgement before the Court of Appeal, the matter went back to the High Court in 2016 which awarded Mr McLean the six-figure sum.
Marshall was adjudicated bankrupt. But it was not the end of his woes.
The civil court proceedings sparked a police investigation and charges of impairing a computer system and interfering with a computer system were laid.
At sentencing this week, the court heard Marshall had written a piece of "malicious code" into the program he handed over to Mr McLean.
It effectively acted as a denial of service and was designed to lay dormant until the defendant’s access to the server was removed by his colleague.
"While users could still trade on the system they could not compare various historic currency rates to assist in predicting trading patterns," a summary of facts said.
Programmers spent four weeks constructing a solution then a further three months testing it.
They painstakingly tested and verified 45,000 lines of code, the court heard.
Crown prosecutor Robin Bates said the acts by Marshall were "deliberate and malicious" and had serious repercussions for the victim.
Mr McLean incurred losses of about $120,000, which would not be recovered.
Defence counsel John Westgate stressed his client had no previous convictions and there was no risk of him reoffending.
Judge John Macdonald said the charges Marshall faced rarely came before the court.
It was clear his conduct was intentional and designed to cause harm, the judge said.
He accepted, though, from a number of character references, Marshall was well thought of in the community.
Judge Macdonald sentenced him to six months’ community detention and 250 hours’ community work.
