Ross Gibson used Twitter to sent a picture making remarks about a young Celtic fan as well as making crude remarks about Scott Brown’s late sister.
The Aberdeen FC fan went on trial at the city’s sheriff court yesterday, having previously denied causing a reasonable person to suffer fear or alarm with the threatening and abusive behaviour.
However after a failed bid by his defence agent to have the police evidence thrown out Gibson was forced to stand before the sheriff and plead guilty.
The 20-year-old, of Aberdeen, was charged following the Parkhead clash between Celtic and Aberdeen on March 1.
During the trial the court heard evidence from police constable Christopher Gardiner, 31.
He detained Gibson after tweets taken off his Twitter page started circulating online.
They included a picture of a Celtic player with a young disabled fan, above which Gibson wrote an offensive remark.
Other tweets included sick remarks about Scott Brown’s sister Fiona, who lost a battle with skin cancer in 2008 aged just 21.
One of the tweets made reference to her being “in hell” with Celtic legend Tommy Burns, who passed away just two weeks before her due to the same disease.
PC Gardiner read out a transcript of the police interview to the court, during which Gibson had admitted writing the tweet about the young Celtic fan.
But he claimed he was actually talking about one of his pals.
Gibson told the police: “Yeah, I wrote that but it wasn’t about him. I was pretty intoxicated. It was about a friend. Nothing about someone with a disability.”
The tweets caused outrage at the time and the court heard that Gibson was forced to shut down his Twitter account just hours after posting the messages.
When asked by police if he understood why there had been such a backlash, he replied: “There’s a disabled person in the picture and I wrote ‘disabled piece of shit’.”
Gibson claimed the posts were only meant to be seen by his friends.
During the police interview he told officers that he had been “immature and disgusting” and apologised for his behaviour.
However after the Crown case concluded Gibson’s defence agent Paul Barnett tried to argue that the police interview - the sole evidence led by prosecutors - should be inadmissible.
He claimed Gibson had not reaffirmed to officers that he understood he did not need to answer their questions during the initial interview.
However Sheriff David Hall said he was “entirely satisfied” that the retail assistant had understood the caution at the start of the process.
Gibson admitted threatening and abusive behaviour by sending messages of an offensive, sectarian and indecent nature.
The offences were said to be aggravated by prejudice of religion and disability.
Sentence was deferred until January for reports and Gibson was released on bail.
The sheriff added: “The charge that you plead guilty to is a serious one and an unpleasant one.”