The Victoria Police e-crime squad have arrested a 36-year-old man after he allegedly tampered with speed and red light infringement data from 2010 and 2011.
The man is understood to be a former employee for the service provider who manages the speed and red light camera data.
A Victoria Police spokeswoman said they could not name the provider.
"It is believed changes were made to infringement data after they had been issued to drivers," she said in a statement.
"The data changes have had no impact on any infringement issued in relation to the speed or red light camera system.
"There is no ongoing impact to any infringements to be issued."
She said that all original data remained within systems and the modifications to data were picked up by internal systems.
The changes to the data included date and time offence alterations, along with the lowering of speeds recorded. It is alleged changes were made to 67,541 cases.
The Victoria Police spokeswoman said the man may face charges of unauthorised modification of data under the Crimes Act.
The arrest follows comments by Victoria's Police minister, Peter Ryan, that performance of speed cameras in the state should be reviewed.
Ryan was clocked doing 63 kilometres per hour in January shortlyafter his swearing in as minister.
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