An internet troll who posted “chilling” online messages threatening to kill Harry Potter author JK Rowling and Rosie Duffield, who was an MP at the time, has been spared jail.

Glenn Mullen, 31, of Clyde Road, Manchester, uploaded audio clips in Gaelic threatening to kill Ms Rowling “with a big hammer” and said he was “going to see Rosie Duffield at the bar with a big gun”, Westminster Magistrates’ Court heard on Tuesday.

Mullen had been publicly identified as the poster of the audio clips by an online magazine shortly after they were posted on social media site X, formerly Twitter, in January 2023, the court was told.

He admitted the offences, two charges of sending an article conveying threatening messages, at an earlier hearing.

Handing down two suspended sentences, chief magistrate Paul Goldspring said Mullen’s actions were part of a “modern phenomena” of people on social media sites “hiding behind a keyboard to threaten, abuse or harass people in the public eye”.

In statements read out by the prosecution, the court heard Scottish author Ms Rowling thought the threats “appeared calculated” and “were quite chilling”.

“They made her look over her shoulder and worry about the safety of her family and her children,” the prosecution added.

The court heard the messages made Ms Duffield, who is the Labour General Election candidate in Canterbury, feel “nervous walking around her constituency, where she was visible and easily accessible”.

Mullen gave no comment in an interview on March 10 but made “full and frank admissions” to making the threats at a later interview on October 6, the court was told.

Mr Goldspring handed down two eight-week prison sentences, suspended for two years, to be served concurrently.

He also ordered Mullen to complete a 12-month community order, including 20 days rehabilitation activity requirement and 150 hours of unpaid work.

He said: “There seems to be this modern phenomena that Twitter and other social media and online platforms allow you to say and do what you like – and particularly people in the public eye, lots of people think are fair game.

“Yes, of course free speech is important but there’s also a line to draw in the sand… and you went well beyond that line.”

Mullen was ordered to pay £85 in costs and a £154 victim surcharge.

Mr Goldspring added Mullen was a “man of previous good character” who had “strong views about gender equality”.

In a statement after the sentencing, CPS senior crown prosecutor John Moran said: “The messages uploaded to social media were targeted and very concerning.

“The audio clips have had a significant impact on the two victims, who described feeling upset, worried and distressed when they heard them.

“Nobody has the right to issue threats or abuse, whether that be in person or via social media.”