No further action will be taken against Daily Telegraph columnist Allison Pearson over a social media post.
Essex Police were investigating an alleged criminal offence of inciting racial hatred, but on Thursday confirmed the Crown Prosecution Service had decided not to bring any charges.
The force added that an independent review of their handling of the case is also being launched.
Chief Constable Mark Hobrough, the hate crime lead at the National Police Chiefs' Council (NPCC), will examine how officers dealt with the allegations, after severe criticism from Elon Musk and some politicians including Conservative leader Kemi Badenoch.
Ms Pearson says she was not made aware of the content of the year-old post, which had since been deleted, but suggested it could have been related to the 7 October attacks in Israel or pro-Palestine marches.
Chris Philp, the shadow home secretary, said: "It should never have come to this. The police should not be policing thought or speech.
"Police time should only be spent on criminality or behaviour likely to lead imminently to criminality. I urge the government to urgently change the guidelines on NCHIs [non-crime hate incidents] to stop it happening again."
NCHI reports have long been controversial, with many citing free speech concerns, but Ms Pearson's account of events has been challenged by the force.
She said she was "dumbfounded and upset" when officers spoke to her on Remembrance Sunday about the post on the social media platform X, formerly Twitter.
On her Planet Normal podcast, Ms Pearson described the visit as "chilling" and "the most extraordinary overreach and state intrusion into my private life," adding: "I don't think I did anything wrong".
But responding to those claims at the time, Essex Police told Sky News that its investigation was never for an NCHI, and the matter was always being treated as an alleged criminal offence of inciting racial hatred.
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On Thursday the force again defended their handling of the case: "We're sometimes faced with allegations of crime where people have strong opposing views.
"That's why we work so hard to remain impartial and to investigate allegations, regardless of where they might lead."
In an interview with The Telegraph last week, Kemi Badenoch said it was "absolutely wrong" for police to make enquiries over the social media post.
"We need to stop this behaviour of people wasting police time on trivial incidents because they don't like something, as if they're in a nursery," she said.
Others who have voiced their concerns include Boris Johnson and Liz Truss, who described the incident as "appalling" and X owner Musk, who said: "This needs to stop".
Essex Police said they made attempts to contact Ms Pearson before their visit on Remembrance Sunday.
The force added that they have complained to the Independent Press Standards Organisation (IPSO) over what they call "false reporting" on their investigation.
(c) Sky News 2024: Allison Pearson: No further action to be taken against Daily Telegraph columnist over social media pos