The six-time All-Ireland champion, who lost his own brother John to drug addiction in 2012, was invited to give a Tedx talk at Mountjoy Prison yesterday afternoon.
During his 20-minute address, he drew from his own personal experiences growing up and how his brother’s life was destroyed by drugs.
A well-known advocate for his native Ballymun, McMahon has long been vocal about the impact addiction has on families and communities nationwide.
The GAA legend, who now mentors’ prisoners in Mountjoy, has recently created a pioneering and ambitious incentive for prisoners called ‘Unfucccked’.
The three c’s stand for change, culture and community.
“Unfucccked is a leadership programme and we’re hoping that 120 prisoners will participate over the course of two years,” he told Independent.ie.
“It’s a movement that’s designed to change the culture in prisons, which isn’t being done anywhere else in the world.
“Ultimately prisons and child detention centres are filters to try and get people back on the straight and narrow.
“But there are a lot of things we need to do better and the unfucccked movement we’re creating will act as a new filter to help them believe in themselves again.”
McMahon said the three-hour-a-week programme is already having a huge impact in Mountjoy.
“In the UK, it costs £200,000 to keep a kid in the criminal justice system and only £50,000 to get them out.
“And in Oberstown, we’re spending €340,000 a year per child. It’s obvious that early intervention is very important, but the social inequality in this country is getting wider and wider.
“We need to invest our money in the right way and into communities that need the most help. This is the only way we can make a difference and break cycles.”
It has been speculated that Sinn Fein is keen to secure the services of the All-star defender in the May 24 local elections.
However, the footballer expressed no desire in becoming politically afflicted, saying he can create a bigger impact in his current role.
“I think the platform I have is making a bigger difference than it would politically. I’m a practitioner, not an academic. I want to be in the grassroots making a difference and to get face-to-face with these guys.
“I want to be a relatable person coming from a similar background, showing that I made it through adversity and am making a difference,” he said.
The Dubliner added that his life could have been similar to his brother’s if his GAA coach at Ballymun Kickhams hadn’t seen the potential in him.
“Thankfully I had a person believe in me and saw my potential on the pitch. Maybe if he didn’t inspire me, I would have gone down the same route as my brother.
“If you have any influence in helping people, then do it because you never know what they’re truly capable of.”
McMahon said he was lucky his parents instilled good values in him when he was younger.
“So when people talk bad about me it’s just their opinion and that’s their issue,” he said.
“But for me, I believe in speaking out about these issues because it’s right.
“To think that prison sentences is the only thing that’s going to prevent these guys from committing crimes again, we’re mistaken.
“I think prison is the last option. But I believe the filter in prison has to be changed.
“I’m not saying we need to get rid of prisons, but if we don’t really go after the early intervention, we’re going to constantly have this cycle over generations.”
Education agency SOLAS and The Irish Prison Service came together for the initiative at Mountjoy yesterday, whose speakers shared ideas with prisoners concerning supports that should be put in place to help ex-offenders.
Nikki Gallagher from SOLAS said “Superb work is being done; and people in prisons nationwide are availing of educational opportunities and increasing their skills and knowledge at every level.
“However, education alone cannot ensure ex-offenders will successfully reintegrate into society when released from prison.”