A woman chased after a mugger believing he had taken her phone – but it later transpired the phone was still in her handbag, a court has heard.
The court also heard that the mugger's mother witnessed his arrest and was so outraged with his behaviour that he was lucky the gardai arrived when they did.
Off-duty garda Nathan Burke witnessed Wayne Cunningham attempting to mug Grace Donnelly, who then chased after him. He assisted her and followed Cunningham in his car, rolled down the window and shouted "stop, gardai".
He later continued the chase on foot and ultimately wrestled Cunningham to the ground on Charlemont Street, in Dublin 2.
Garda Jennifer Clancy told prosecutor Monika Leech that Cunningham struggled with Garda Burke as he was trying to restrain him and the garda requested Ms Donnelly to call the gardai.
Ms Donnelly's phone then rang in her handbag and she realised that it must have fallen in there as Cunningham was trying to grab it. Cunningham (25), of French Mullen Flats, Charlemont Street, Dublin 2, received a 12-month suspended sentence.
He had pleaded guilty at Dublin Circuit Criminal Court to attempted robbery at Adelaide Road on March 29, 2011, and has two previous District Court convictions for public order offences.
Garda Clancy said she was on routine patrol at the time when a cyclist knocked on her car window to tell her that he saw a man chasing another man across the Luas tracks.
She then arrived on Charlemount Street to find Garda Burke holding down Cunningham and assisted in arresting him.
Garda Clancy said Cunningham was later brought to Harcourt Garda Station and a search revealed that he had a knife with him.
A victim impact statement from Ms Donnelly stated that she is more cautious and is wary of strange people approaching her.
Garda Clancy agreed with Breffni Gordon, defending, that his client's mother witnessed his arrest and was so outraged with his behaviour that Cunningham was lucky the gardai arrived when they did.
Judge Desmond Hogan described it as "an opportunistic crime that was nonetheless unsuccessful".
He sentenced him to 12 months in prison, which he suspended on condition he keep the peace and be of good behaviour for that time and carry out 240 hours' community service.