''Spiral'': Shane Diehm at Downing Centre Local Court. Photo: Dominic Lorrimer/Getty Images
The police officers stand around a bag of so-called ''hash cookies'' in a Gold Coast unit, joking about how long cannabis remains detectable in the human body.
''I don’t know why I’ve got three weeks off after this, but I’ve got three weeks off,'' Shane Diehm, then a police Inspector, says laughing.
''My eyes are like pinholes so something must be happening,'' another officer says.
A small camera hidden in the unit by Police Integrity Commission investigators records the officers munching away on the cookies as the party gets more boisterous.
A year later, in 2011, when the men were hauled before the Police Integrity Commission, Diehm admitted that he took illicit drugs during the weekend. But, despite having lost his job, he maintains he has no memory of seeing any of his officer mates do the same.
The 49-year-old has stuck to that position and is now on trial in the Downing Centre Local Court for knowingly misleading the commission.
Diehm told the court on Wednesday that when he fronted the commission, he could not remember significant parts of the weekend because of the large amount of alcohol he had consumed. He says he now has no memory of the events at all.
This was part of a ''spiral'' of drinking, depression and post-traumatic stress disorder he experienced despite his rise through the ranks to a position as second-in-charge of the Tweed Heads Local Area Command.
''I was put into a senior position at Tweed Heads, in essence, to pull the police into line,'' Diehm said. ''A lot of people beneath me didn't agree with that.
''I was either at work or I was binge drinking. It could start at any time – midday or before. It could go for two to three days ... maybe a break for coffee or breakfast, and then go again,'' he told the court.
Diehm’s solicitor Tim Watts said while it might seem ''at first blush'' that watching a group of current or former police officers take drugs was ''something that would stick in the mind'', ''the memory can do strange things''.
''This wasn’t a weekend where these guys sat around drinking cups of tea and asking ‘would you like a Scotch Finger Biscuit?’ '' Mr Watts said.
''They went there to get smashed, to get hammered – whatever you want to call it.''
But prosecutor Christian Hearn said Diehm had been sober enough to carry on a conversation and there was no suggestion that he had experienced an ''alcohol-induced blackout''.
''Mr Diehm has a clear and obvious reason to lie,'' Mr Hearn said. ''These were his long-time friends ... and they were police officers.
''The consequences of revealing that [drug-taking] would quite frankly be career-ending. His claims not to remember simply don’t stand up to scrutiny.''
Diehm will be sentenced for misleading the Commission in relation to his own drug-taking in the coming weeks. A decision will also be handed down at this time regarding his claims not to have seen the other officers take drugs.