A high court in the UK ruled on Friday that police should not have visited a man who sent out “transphobic” tweets at his place of work and that they had a “substantial chilling effect” by doing so, the Guardian reported.

Police told 54-year-old Lincolnshire man and former cop Harry Miller that no crime was committed but his tweets were recorded as a “hate incident.” According to the Guardian, the high court of London found that Humberside police acted with “disproportionate interference” by confronting him at his place of work but upheld rules that allowed them to record the tweets as hateful.

Guidelines by the College of Policing, a professional policing organisation in the UK, state that a transgender hate incident is “any non-crime incident which is perceived, by the victim or any other person, to be motivated by a hostility or prejudice against a person who is transgender or perceived to be transgender.” Among 30 other tweets police identified as anti-trans, Miller had retweeted a poem containing the lines “Your breasts are made of silicone, your vagina goes nowhere,” according to the Telegraph, with Miller denouncing “transgenderism.” The Guardian previously reported that one of the other tweets read, “I was assigned mammal at birth, but my orientation is fish. Don’t mis-species me. Fuckers.”

Mr. Justice Julian Knowles wrote in his ruling that nonetheless, the “tweets were lawful and there was not the slightest risk that he would commit a criminal offence by continuing to tweet,” and when the police visited him at work it was clear Miller “was being warned not to exercise his right to freedom of expression about transgender issues on pain of potential criminal prosecution,” the Guardian reported. However, Knowles described the College of Policing guidelines as “legitimate.”

According to ABC News, Miller addressed reporters outside the courtroom by calling the ruling “a watershed moment for liberty,” adding “go forth and tweet without fear.”

“It is a strong warning to local police forces not to interfere with people’s free speech rights on matters of significant controversy,” Miller’s solicitor, Paul Conrathe, told the BBC.

UK feminists are not always aligned on trans rights issues in the UK, where the trans-exclusionary radical feminist movement has a strong foothold and is covered favourably by the media. UK law also requires that trans people undergo medical assessments that return a diagnosis of gender dysphoria, provide evidence they have lived as another gender for two years, and “get permission from their spouse or end their marriage” to legally change their gender, per CNN. The UK government has been considering reforming those laws, the topic of which Miller was weighing in on. One trans rights campaigner told the BBC she was worried the court had failed to weigh in on what kind of anti-trans rhetoric is protected or not.

“I think trans people will be worried it could become open season on us because the court didn’t really define what the threshold for acceptable speech was,” trans advocate and Trans Media Watch co-founder Helen Belcher told the BBC. “I think it will reinforce an opinion that courts don’t understand trans lives and aren’t there to protect trans people.”