Fox's cop is no sure shot

Our TV critic Aaron Barnhart rates tonight's premiering show The Barnhart scale, from best to worst: Don't Miss, Has Potential, Needs Show Doctor, D.O.A. (Dead on Arrival). Needs Show Doctor "Ryan Caulfield: Year One" is a hybrid of a shopworn TV genre (the cop show) and this year's big program fad (the coming-of-age show). Ryan Caulfield is 19, he lives at home with his mom, and he's a rookie cop in Philadelphia. It's a real contest between Ryan (Sean Maher) and that rookie cop on "Third Watch" to see which one's dumber. But for unconventionality, this wins hands-down. You see, when Ryan's not getting shot at by urban punks, he has this other life with his suburban friends who went off to college. It makes for a couple of interesting scenes, but I don't see much of a future for Ryan's old pals. And running him through a few cliched police scenes doesn't make Ryan any more appealing a character. (7 p.m. Fridays, Channel 4) For full coverage of the fall season, visit the TV Barn Web site www.tvbarn.com