Judge Sean MacBride, who is from Moville, said the speed detection vans, operated by a private company, were “bringing the law into disrepute”.
Since it began five years ago, the outsourcing of speed detection by gardaí has been controversial.
Judge MacBride threw out all prosecutions before Monaghan District Court involving ‘Go Safe’ vans, saying “the chain of evidence was inherently flawed” and there were “defects in the serving of the summonses”.
‘Go Safe’ vans are operated by a private company, on behalf of An Garda Síochána.
Judge MacBride said they often operated just inside or outside 30km/h zones, in places where detecting offences was like fishing in a “goldfish bowl”.
This was rejected by an inspector from the Garda Fixed Penalty Office, who was adamant they were in “black spot” areas and “saving 25 lives a year on Irish roads”.
The ruling is the latest setback for ‘Go Safe’ vans, coming after the dismissal of 98 such cases in Co Clare last month.