The 17-year-old, who accepted his presence was intimidating, was released on six months of supervised probation today.
CCTV footage emerged of a 17-year-old girl at Howth junction station falling between the platform and a stationary train on April 1 last year. She was helped back onto the platform by her friends and staff.
Investigating gardaí obtained directions from the Director of Public Prosecutions (DPP) and charged three youths aged 17 with violent disorder.
One of them had an additional charge for assault causing harm to the girl knocked off the platform; his case has been separated and sent forward to the Circuit Court for trial.
Judge Paul Kelly held the two other boys had peripheral roles, and he accepted jurisdiction for their cases to remain in the Dublin Children's Court.
They pleaded not guilty and were convicted after the case went to a full hearing earlier this month.
The prosecution had video footage from the station's CCTV system, a security guard's body cam, and evidence from a second teenage girl who interacted with the group.
The court heard gardaí identified them with the help of confidential information from the public.
Judge Kelly was told security put a group of about 10 youths off a train due to anti-social behaviour complaints.
One of the 17-year-old boys swung his foot at a girl from his bike, making contact with her head.
She described it as "daunting", and "one of them lunged at me".
That happened shortly before a related incident in which a second teenage girl was knocked head-first from the platform under the stationary train.
An OCS security man raised the alarm with the train driver and pulled that girl back onto the platform.
State solicitor Mairead White submitted that the evidence supported the charge, established the youths acted together, and was a "joint enterprise".
Judge Kelly held there was a clear threat of violence, and also the footage showed lunging, an attempt to "body-check", several were making gestures, and one of the youths made physical contact with the witness as she tried to get to the train.
He noted the evidence of a security guard that the group was “intimidating people”.
Video evidence showed them hurriedly fleeing the station.
The court heard gardaí searched the two boys’ homes and recovered clothing. Garda Kevin O’Boyle said they were identified as a result of media attention. He added that a lot of information came to the garda confidential information line from people who were “reluctant to give statements”.
Judge Kelly noted they had no prior criminal convictions.
One of the boys interviewed by gardaí identified himself in the video evidence holding an electric bike. When gardaí asked him why he left after the girl fell off the platform, he replied: "I felt bad I didn't help her; I was in shock."
“In situations like that, you just walk away. You don't get involved," he said. However, he conceded that the group probably intimidated others.
Today the Probation Service furnished a pre-sentence report on that youth to the court. Defence solicitor Aonghus McCarthy asked the judge to note that it was positive and that his client was in employment.
Judge Kelly imposed a six-month probation bond. The teen must continue to accept guidance from the service to divert him from re-offending; otherwise, gardaí could re-enter the case, and he could face a harsher sanction.
Sentencing of the co-defendant, who swung his foot at the girl’s head, was adjourned for a month.