A barefoot angler hurled an obscene tirade of anti-English abuse at police even after he was locked up in a cage.
Ian Doyle, 26, admitted using homophobic insults and racial slurs in his prolonged X-rated rant.
Perth Sheriff Court heard that officers investigating reports of a “suspicious” van near Killiekrankie on the A9 had found him at the roadside with no shoes on.
Bill Kermode, depute fiscal, said that that Doyle, of Overton Crescent, Denny, appeared to be in an “agitated state”.
He was unsteady on his feet and slurring his words and became aggressive when the police asked him what he was up to.
When told he was being arrested for his behaviour, he launched into a lengthy rant and told an officer: “I’ll sort you and your kids out.”
Doyle continued his outburst from the back of the police car en route to Perth and his heckling became so bad that the officers had to stop at Pitlochry to transfer him into a cage in the back of a police van.
That did not halt the storm of abuse, however, and he started banging himself against the walls of the van.
Doyle, who had been on a fishing trip with friends at the time, admitted the offence on September 3.
Sheriff Christopher Shead said: “What can we do with Mr Doyle other than locking him up?”
The sheriff deferred sentence until next month for the preparation of background reports.