Ms. Brooks and her husband, Charlie, a racehorse trainer who was also acquitted of charges of hiding evidence (along with his pornography collection) from the police, left the court in a taxi without offering comment. The other people acquitted were Ms. Brooks’s former personal assistant, Cheryl Carter, 50; Mark Hanna, 51, a former security director; and Stuart Kuttner, 74, a retired managing editor. The jury is still considering further charges against Mr. Coulson and Clive Goodman, 56, the former royals editor of The News of the World, on charges related to paying police officers for access to royal telephone directories.

At times Britain’s phone-hacking scandal has felt like a badly scripted television drama, with all its barely believable turns and twists: the father-daughter-like relationship between Mr. Murdoch and Ms. Brooks; her $17.6 million severance payment from News International (since renamed News UK); a steamy love letter to Mr. Coulson that was read in court; and a tabloid-style defense strategy that featured the kind of highly personal revelations for which the tabloids Ms. Brooks once edited might have paid six figures, like the adultery and the daughter she had by a surrogate mother.

“My personal life was a bit of a car crash,” she said in the witness stand early on.

Ms. Brooks was a longtime protégée of Mr. Murdoch’s and has been called his “fifth daughter” in the British news media. At 31, she became editor of The News of the World. A decade later, she was running his British newspapers. All the while, she accumulated a glittering list of friends. Mr. Cameron, a neighbor in the Oxforsdshire countryside, rode her husband’s horses.

The tabloid culture revealed in the trial was one in which paying as much as $240,000 for a single article was deemed justified, if that meant beating rivals, even at other Murdoch papers, to a scoop. In one striking example, The News of the World tracked down the prostitute Divine Brown, who had been arrested with the actor Hugh Grant in Los Angeles in 1995, and offered her 100,000 pounds, or about $160,000, for an exclusive. “Hugh Told Me I Was His Sex Fantasy,” the resulting headline read.

The testimony was such that Ms. Brooks is unlikely to fully recover her reputation — and the trial has humbled a once mighty and swaggering tabloid press, regardless of the outcome. Newspapers may become a little more boring, experts said, but at least they appear to stay within the law these days.