His step daughter was being bullied.
It had been going on for months, to the point where she was afraid to go to school.
Mark Bladen had had enough, and wanted initially to simply give the young man an "Old Fashioned Talking To," but when he confronted the bully, the young man looked back at him and smirked, and Mark lost his cool.
He went after him, and of course someone was taking video, which quickly went viral, and divided the world.
He has received a LOT of support, but also a lot of backlash too.
Was the Dad wrong? What would you do if it were your daughter being bullied and this happened to you?
Mark was arrested, he was charged and plead guilty to one count of assault causing bodily harm.
While the step-dad avoided a criminal conviction, he had to pay $1,500.
60 Minutes Australia (Where the incident occurred) will air a segment on it this Sunday.
You can see the entire video from the skate park by CLICKING HERE