Actress Kristen Bell and her husband Dax Shepard have confronted an owner of a paparazzi photo agency and one of his snappers during a heated debate on U.S. television, in an effort to stop photographers from taking pictures of celebrities' kids. For the past couple months, the Frozen star and her new husband have been on a crusade to urge fans and other celebrities to boycott tabloids which feature unapproved pictures of stars and their children, in a bid to protect the youngsters from the aggressive paparazzi. Many celebrity parents like Alyssa Milano and Minnie Driver have joined the cause, and some media outlets including People magazine, Entertainment Tonight and JustJared.com have agreed not to buy snaps from agencies that take pictures of kids. But the couple have yet to strike at the heart of the problem and convince a leading agency to join their fight. Bell and Shepard, who are parents to 11-month-old daughter Lincoln, confronted AKM-GSI photo agency boss Steve Ginsburg and reporter Christian Zimmerman during a taped showdown on U.S. entertainment news programme Access Hollywood, and the two sides butted heads, with neither backing down. Bell stated, "I'm telling you as a mom, when I'm holding my baby, your foot soldiers are nasty. What they might be doing is 'legal'. But when I get off an airplane and I'm walking to my car and it's dark, and I'm with my baby by myself, it's terrifying." Shepard added, "If you don't have an ethical issue with that, then you don't have ethics." But Ginsburg was quick to defend himself, calling Bell 'hysterical'. He insisted, "It is our constitutional right to take the picture!" When asked if they would ever stop taking kids' photos, Zimmerman replied, "To be frank about business, no." Later Bell explained why they decided to begin the fight against the snappers in the first place, admitting, "I don't think under any circumstance a child should have a price on their head. I think it should be a sacred time when you grow up and if you don’t choose to be in this business, like the children don't, we've got to leave them out of it. "And I feel like I just wanted to start a conversation with other people who care about the welfare of children and let them know the bad behavior that actually goes into getting the shots." The celebrities did win a huge battle over the paparazzi last year (13), when Hollywood mums Halle Berry and Jennifer Garner joined forces to fight for new legislation to protect the kids of stars. Their successful campaign led to new laws that restrict what photographers can do around children.