A mayoral task force in San Francisco has endorsed giving clean needles to drug addicts to slow the spread of AIDS, but police and health officials said that no such city program was likely without changes in state law. Police Chief Frank Jordan said he supported such a program, but he added that the city could not begin one now because state law bans giving needles to anyone without a doctor’s prescription. “We have to experiment with all kinds of creative ways” to stop acquired immune deficiency syndrome, Jordan said. However, “it is quite clear that it is a misdemeanor,” he added. Public Health Director David Werdegar said he was trying to determine whether he can get “administrative permission” for starting a small-scale project that would allow the distribution of clean needles to addicts.