The Fair Work Commission has savaged the defence department and its “vague and contradictory IT policies” over the dismissal of Darko Gmitrovic last year, after he was accused of spending most of his working days surfing the web.

Despite the involvement of two senior defence disciplinary bureaucrats, the conduct of the department was described as “bizarre” at times, with senior public servants falling back on “poor excuses” when called to account by the workplace umpire.

Mr Gmitrovic found himself in his bosses’ sights in January 2012 when he was investigated over excessive internet use, with defence alleging he was averaging 1822 website visits per day.

It was also alleged that he had downloaded “anonymizer” software that allowed him to hide his browsing activity from his employer and to bypass security surrounding defence’s restricted network.

In his defence, the APS 5 bureaucrat ridiculed the allegations and pulled apart spreadsheet evidence presented by his accusers that purportedly showed him clicking on one site 331 times in seven minutes.

“I would have had to be mentally disturbed to spend seven minutes opening one and the same site 331 times,” Mr Gmitrovic wrote.

But the IT expert’s response only got him into deeper trouble with Danielle Pokoney, a senior bureaucrat with defence’s conduct and performance unit, who told Mr Gmitrovic he was arrogant, condescending and disrespectful of the disciplinary process.

Ms Pokoney concluded Mr Gmitrovic had breached the Australian Public Service code of conduct, had engaged in deceptive conduct and he deserved the “sternest of sanctions”.

He was sacked in August.

But when Mr Gmitrovic took his unfair dismissal case to a Fair Work Australia hearing in Sydney in March, the defence department's conduct unravelled.

Mr Gmitrovic did not deny using an anomymizer, but said it was a website, not a download as alleged and he used it to secure his work-related activity from any outside attempts to monitor the department's work.

He also argued that internet browsing, particularly of real estate websites, was of great use in his work Defence Estate Management System.

There was no rule against using an anonymizer in defence’s internet protocols, which the commission found were “vague and contradictory”.

Defence’s lawyers tried to portray Mr Gmitrovic as dishonest but Commission Senior Deputy President Jonathan Hamberger was not convinced.

Although the sacked bureaucrat was “certainly argumentative” and “rather literal-minded, verging on the pedantic” Mr Hamberger accepted Mr Gmitrovic as an honest witness.

The commission found it was bizarre that the investigators had not questioned Mr Gmitrovic’s supervisors and colleagues about his web surfing and relied on “poor excuses” to defend the failure to do so.

“The investigation into the applicant’s alleged misconduct, and the process used to dismiss him, was an extraordinarily drawn out affair,” Mr Hamberger wrote.

“It was both amateurish and unfair.”

After it was agreed that Mr Gmitrovic did not want to return to his job and the defence department did not want him back, the commission awarded him $22,798, equal to 16 weeks salary.