A former police officer described as the ‘worst rotten apple in years’ has denied earning tens of thousands of euros by leaking details of criminal investigations to gangsters.

Mark M. appeared in court on Monday to answer charges that he laundered €79,000 that he received for passing on information from confidential files. M. admitted that he had trawled police computers as a ‘hobby’ but denied selling the information to criminals.

M. spent six years in police service until he was arrested in September 2015. He was alleged to have arranged ‘subscriptions’ starting at €5,000 a month for criminals to obtain information held in the BlueView information system.

Police found €4,000 in cash at M.’s home in Weert. But the former officer said the cash came from a business venture in Ukraine, his girlfriend’s native country, where transactions are commonly made in cash.

Former police chief Gerard Bouman earlier described M. as ‘the worst rotten apple in years.’ It emerged that M. was one of more than 100 police staff who were given access to confidential files despite failing the screening checks. ‘I am especially concerned that this could have happened because of mistakes by police personnel,’ Bouman said shortly after M. was arrested.

In court, M. said the Rijksrecherche, the police’s internal investigations unit, had ‘taken the whole story out of context’. He claimed most of the money came in the form of a €60,000 loan from his partner, though he admitted he had no idea where she had got it from.

‘It’s normal in Ukraine to have large sums of money in cash,’ he said. ‘Nobody asks where it comes from. If someone buys a Bentley in Ukraine, his neighbours think he’s doing good business. In the Netherlands they go and ask the police where he got the money from.’

M. said the impact of the case and the publicity surrounding it had hindered his efforts to start up a telecoms and security business in Ukraine. He added that his dismissal from the police force was the subject of another legal dispute.