"I mean, he's beat -- they're beating the hell out of him, you know?" Gibson told "Good Morning America" special contributor Cameron Mathison. "So you know, I love the guy. He's full of flaws, like all the rest of us. And he's getting a rough time.
"Ask any human being walking on the planet, 'Have you ever done anything that you're not too proud of?' and I think most people will say, 'Yes. I've done a few things I'm not too proud of.' And a lot of times the most difficult thing about all of that is being able to forgive yourself. ... Geez, I want to watch him play golf."
It's been seven years since Gibson's last major movie, but the world-famous actor will be back in the familiar shoes of a grizzled, driven cop for the upcoming thriller "Edge of Darkness," which opens Friday.
In the film, Gibson plays a police officer whose daughter is gunned down before his eyes. The tragedy fuels the cop's turn from a straitlaced officer to an avenging force.
"That's the emotional core of the film ... the father-daughter relationship," Gibson said. "Probably the fact that she's tragically taken from him and the fact that he probably wasn't such a great dad while she was alive, that he's trying to make it all up to her posthumously -- that's the tragedy of it, I think."
No stranger to the father-daughter relationship, Gibson, already a father of seven, recently added a baby girl to his brood.
"Wow, you know? It certainly brings back a few memories. A new life is so precious, and it's so great to watch ... and it's uncompromising. It's a force bigger than -- it's big," he said.
Mel Gibson: From Obscurity to Scrutiny
Since he had the fatherhood connection down, Gibson said the other major part of the role that took some time was perfecting the accent for an Irish Boston cop.
"It really nailed it when the guy who was teaching me the dialect said something like, 'It's kinda like a tough-talking cartoon dog.' And I thought, 'Well, that's good, you know?' So I just kind of always imagined myself as a tough-talking terrier," Gibson said. "And oddly enough, it's interesting that [director] Martin [Campbell] would cast me with people who were like the size of basketball players. So if you watch the film, I'm in two shots and I'm always like underneath their shoulder, like sort of yapping up at them."
Now an international superstar, Gibson said he first realized he was losing his anonymity in his mid-20s.
"I think I was in a hotel. I was about 25, and I had some guys call up from the lobby saying, 'Hello, Mr. Gibson. We're down here. We're waiting for you. Could you come down and sign some pictures?' I thought, 'Come on, somebody's putting me on.'"
They weren't. After he signed their pictures, the group refused to stop following him around.
"I knew that I'd lost something," he said. "I knew that I had lost personal anonymity, and that I would never have it again. It's a very precious thing to lose."