A house party reveller left a student with nose and face in- juries after a "nasty, unprovoked attack", a court heard.
Conor Hynes (20) lost control and assaulted Leaving Cert student Sam McKay (18), who had intervened in a row to ask if everything was all right - writes herald.ie.
The victim was so traumatised that he could not concentrate on his studies afterwards and "did not get the results he deserved".
Judge Michael Walsh ordered Hynes to pay €3,000 in compensation and applied the Probation Act, leaving him without a criminal record.
Dublin District Court heard Hynes had also gone on an offender reparation programme.
Hynes, of Templeville Drive, Templeogue, pleaded guilty to assault causing harm to Sam McKay last January 8.
The incident happened at a house party in Rathdown Park, Terenure.
Hynes punched Mr McKay several times in the face and kicked him when he was on the ground.
The victim had headaches and dizziness which resolved after a week.
However, the court heard that he suffered from low mood and lost interest in his school, sports and social activities.
The victim's father, Eamonn, said that although his son completed his Leaving Certificate, he had been unable to focus on his exams and did not get the results he deserved or the sports scholarship he had hoped for.
"It is fortunate he was not more severely injured," said Judge Walsh.
He noted the defendant's apology, previous good character and co-operation with the garda.
Mr McKay had incurred medical expenses of €2,500, and the accused had already paid him €3,200.
"We have closure on it now after all Sam has gone through," his father said outside court after the hearing.
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