Trouble started between mum-of-11 Emma Green and eldest son Scott when he revealed he was gay and in a relationship with a man at a family party.
As the evening wore on, Green called her son “a pf and a gay b****”, prosecutor Lisa Marshall told Perth Sheriff Court.
Police were called as the arguments became heated and, as they arrested Scott for suspected assault, his mother walked up to them and punched her son in the head.
Ms Marshall said: “She shouted, ‘You bender, you take c**** up the a***. You’re nothing but a dirty q****.’
“Police told her she was under arrest and she replied, ‘I’m homophobic. I don’t care – I hate the little gay b******.’”
PARENTS SHARE TOUCHING ONLINE RESPONSES TO THEIR CHILDREN COMING OUT AS GAY
Sheriff Lindsay Foulis ordered her to pay £100 compensation to her son and fined her £200.
He told her: “If she hadn’t been so stupid as to strike her son when he was being held by police officers, nine times out of 10 this wouldn’t have seen the light of day.
“You can’t act in this way and it was added to by the fact it was prejudiced.”
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Assault charges against Scott were dropped and lawyers have revealed that there is "no ongoing ill-feeling" between mother and son.
Green claimed last night that she lashed out in self-defence, not because her son was gay.
She added: “I just wish none of this had ever happened.
“I’ve got enough on my hands looking after the rest of the family.”