When it comes to his films and his family, social responsibility drives director-actor Tim Robbins.

Best known for Bull Durham and The Shawshank Redemption, Tim Robbins, 40, returns to the screen this spring after an 18-month break as a stay-at-home dad. The actor, raised in an activist family, feels a duty to raise a stink. He does it through his movies, such as the death-penalty drama Dead Man Walking, and controversial political acts with his longtime mate, Susan Sarandon. The unconventional (and unmarried) couple have made a mission of teaching their kids that social protest is an obligation.

His next movie is Arlington Road, a thriller that echoes the Oklahoma City bombing and raises hard questions about domestic terrorism.

Q: How will your new movie play in Oklahoma?

Tim: It'll be hard to watch. But anything that poses a question is helpful. [People prefer to assume Timothy McVeigh acted alone because] we sleep better that way. It's over. We got him. He's behind bars. But the truth is, there are people like him, armed to the teeth, waiting to overthrow the government.

Q: Your dad, a member of the Highwaymen folk group, was a peace and civil-rights activist. What are your earliest memories of protest?

Tim: My sister was arrested in college for protesting the Vietnam War, and my parents were very proud. They said, "It took courage for your sister to do this." I was 10 or 11. So many people take things for granted that are a direct result of protest. If you have a 40-hour week, union protests made that possible. The right to vote for women and blacks came from protests.

Q: You and Susan were criticized for making a plea at the 1993 Academy Awards for HIV-infected Haitian refugees held by the U.S. government. Do you regret doing it?

Tim: We used something that is usually a celebration of hairstyles and clothing to do good. It was appropriate for that evening, since nearly everyone in that audience was wearing a red AIDS ribbon. A lot of people said we went over the line. The outrage was so strong. But I'd absolutely do it again. Our act of protest took just 26 seconds and actually led to change.

Q: You and Susan have three children, ages 6, 9 and 13. How do you let them know it's OK to question authority?

Tim: You do it by allowing them to question you and your authority, without punishing them for it.

Q: And how do you teach kids social responsibility?

Tim: Through actions. If you're walking down the street and someone asks you for money, it's hard to know if he's a junkie or if he's hungry. So what do you do? You buy him a sandwich.

Q: Like you, your kids are growing up in New York City's Greenwich Village. Why not suburbia?

Tim: It's important to hear all kinds of languages at an early age, to see all races, to mingle with people from different places. All these things make you much more understanding than if you came off the bus from Whiteville, USA.

Q: Why'd you stop working for 18 months?

Tim: I had enough money. My career was stable. I felt if I didn't do it, it'd be selfish. Staying home was really great. I got to know my kids better. It was the little things -- being there after school, cooking them meals.

Q: When you went back to acting and directing, how did you explain it to your kids?