LONDON — After months of hearings, a long-awaited report on the behavior of British newspapers embroiled in the phone hacking scandal recommended on Thursday a new system of press regulation that would be backed by parliamentary statute, setting up what threatened to develop into an acrimonious political debate about curbs on Britain’s 300-year-old tradition of broad press freedom.

Weighing in at 1,987 pages in four hefty volumes, the report reprised nine months of testimony by 337 witnesses at an inquiry led by Lord Justice Sir Brian Leveson. The judge was appointed by Prime Minister David Cameron to lead a review of newspaper ethics and practices at the height of the scandal that erupted around The News of the World, a now-shuttered Sunday tabloid owned by Rupert Murdoch’s British newspaper subsidiary.