"Considering I was only supposed to be in the pilot, it's miraculous five years later to be part of the regular cast," Howell told United Press International in a recent phone interview.
"A lot of that has to do with luck and the show has changed a lot," the 46-year-old actor explained.
"Originally, we were a divided show between the detectives and the police officers and now we pretty much focus on the cops, other than Regina King's [Detective Lydia Adams] character. I think that had a lot to do with it. But, for me, it's an opportunity to do really good work, week in and week out.
"I've got a great relationship with the actors and a great relationship with the writers and my responsibility has changed a little bit in terms of you know where you're going to be for four or five months out of the year. It's just a wonderful opportunity to grow as an artist and grow as an actor. And, each and every week, come in and give it your best; that's been awesome."
Having a complicated, controversial character like police officer Bill "Dewey" Dudek to explore over an extended period of time is also greatly appealing, Howell said.
"It's a challenge each week," the actor acknowledged about his risky role. "He says things that make a lot of people cringe. At times, he's a racist. At times, he's not. At times, he's a misogynist. At times, he's not. There are times when he is very responsible and there are times when he's not. You never really know what you're going to get with him and I really find it a challenge each and every week to, in a way, do despicable things and say things that are unfair and unlikable, but there are times when I really try to find a balance within him. To do those things and still maintain a likability, and that's just been incredible as a performer and as an actor. I've really enjoyed coming to work and making those choices and finding a way to play a guy who might not always be likable, but make him lovable. That's the real challenge."
Howell said the working or retired police who are always on the show's set are a tremendous resource in helping the actors, producers and writers make "Southland" as authentic as possible.
"We are surrounded by real cops," Howell emphasized. "Any cop you see in a uniform outside of the four of us -- Shawn Hatosy, Michael Cudlitz, Benjamin McKenzie and myself -- all the other cops are all real cops, so there is a certain responsibility that we all feel and take very strongly to do the right thing. Whether we're kicking down a door and drawing our weapons or writing out a citation, there are certain dos and don'ts that come along with the responsibility of being a cop.
"We've got great technical advisers that are making sure we're doing the right things at all times. Most of our stories come from events that really happened, so many times we'll be in the middle of a scene and the cops we're working with will come up and say, 'Yeah, I remember when this happened four years ago.' ... And you hear the real account of what actually went down when you're shooting a sequence. So we're constantly reminded by the people who do this for a living, that are actually facing the opposite end of the barrel of a gun for a living. ... Every day when I go in, I'm so impressed by the people who do this for real and I feel a certain amount of responsibility toward them to do things properly and I think the rest of the cast would say the same thing."
Howell said he knows he and his collaborators are doing a good job because of the feedback they receive from real cops.
"The best of the best have really embraced the show," the actor said. "We have so much support from the Los Angeles Police Department and vice versa. I spend a lot of time hosting LAPD events and the rest of the cast does the same thing and we work with these people so closely now and I have so much more respect for police officers and what they do than when I started the show.
"I don't think the general public really knows what these people go through day in and day out. I sort of wish they had the experience we've had over the last few years to really understand that. Because there's a lot more respect I have for these people and for their jobs and the stress and the hardships they go through on a daily basis.
"You never know on a simple call -- whether it's a domestic violence call or pulling over a car -- you just never know if the person you're dealing with if it's their last day and they're going to go out in a blaze of glory and bring you down with them."
Howell is best known for his roles in the films "E.T.," "The Outsiders," "Red Dawn," "Soul Man" and "Secret Admirer," "The Hitcher," "Tank," "That Night," "Gettysburg," "Gods and Generals" and "The Amazing Spider-Man," as well as for his guest appearances on TV's "Hawaii Five-0," "Revolution" and "Castle."
He is married and the father of three children.
The 10-episode, fifth season of "Southland" is to kick off Wednesday night on TNT.