A man who hit a service station attendant with a tyre iron during a violent robbery has spoken of going "off the rails", turning to alcohol to drown out his grief after a visit to his mother's grave for the first time in years.
Leigh Coulter, 24, is less than a week away from being sentenced over the aggravated robbery of a Caltex service station in Kaleen in August last year.
Coulter jumped the counter wearing a balaclava, and forced the attendant to hand over cash.
Once he had the money, he hit the man with the tyre iron, the court heard.
A second man has been charged over his alleged role in the robbery, but Coulter denied he was involved.
A passer-by intervened, tackling Coulter to the ground and forcing him to flee.
Coulter told the court on Thursday that he was in the grip of a downward spiral of alcohol abuse, sparked by a visit to his mother's grave on her birthday in July last year.
He described how his grief consumed him, and how he "hit rock bottom again".
He said he used alcohol to "try and drown it out, but it led to this".
Coulter told the court he still can't figure out why he robbed the service station, and sincerely apologised for the physical and psychological damage caused to the attendant.
Coulter is also being sentenced for headbutting and punching a man who he blamed for sending him to prison outside the Belconnen library in April.
Coulter said to the man "I did six months jail because of you", before headbutting him and punching him repeatedly, the court heard.
Supreme Court Justice Richard Refshauge is expected to sentence Coulter on Wednesday.