FOUR months after the videotaped beating of a black motorist by police here, independent commission findings of widespread racism, repeated use of excessive force, and mismanagement in the Los Angeles Police Department could lead to the broadest reforms in the city's history.More than half of the City Council endorses departmental reforms recommended this week in a report by the 10-member commission. But overhauling the police department will be difficult, requiring cooperation between the mayor, the police department, city voters, and City Council members. "We could very well see a needed sea change, but there is still a long way to go," says Sherri Jeffe, a political scientist at the Claremont Graduate School. After the Watts riots 25 years ago, a similar commission, the McCone, issued recommendations that were never implemented, she notes. A member of that commission was Warren Christopher, the former deputy secretary of state who chaired the current commission. "Christopher knows the history of such recommendations and his plan is clearly not to fade away this time," Ms. Jeffe says. The commission will reconvene in six months to report progress to the public. Among the commission's findings: * Police Chief Daryl Gates should begin transition toward retirement and successors should be limited to two five-year terms. (Such term limits would require a voter-approved amendment to the city charter.) * Some Police Commission members should resign and the panel should be strengthened. (Police Commissioners Melanie Lomax and Sam Williams offered resignations Tuesday.) * A "siege mentality" alienates officers from the community. Policing style needs to be changed. The disciplinary system is "skewed" against citizens making complaints and must be restructured. "We will not rest until the Christopher Commission has changed the way we police our city," said Mayor Tom Bradley, calling for immediate implementation of all recommendations without change. Reactions in most corners have been generally positive, with the exception of Police Chief Daryl Gates, who has said he is "not going to just run away." The commission united a 3-member panel appointed by Chief Gates and a 7-member panel appointed by Mayor Bradley. Ms. Lomax told reporters "the most compelling [thing] about this report is the vindication it brings to the minority community after years of compliant suffering, knowing that there was a racist, brutal element of the department and not being able to prove it." The Christopher Commission report also found a "problem group" of dozens of police officers who use excessive force and released transcripts of racist and sexist messages sent on police computers.