PLATFORM : 'Unduly Harsh' Former Los Angeles police officers Laurence M. Powell and Stacey C. Koon, convicted last month in the Rodney G. King case, are now free on bail pending their appeal. When U.S. District Judge John G. Davies reversed himself and granted bail, he said he relied in part on a pursuasive opinion on the subject issued last Friday by federal appeals court Judge STEPHEN REINHARDT. Following is an excerpt from Reinhardt's opinion: