Charlie Gilmour, the son of Pink Floyd guitarist David Gilmour, has been handed a 16-month prison sentence for going on a destructive rampage during a student fees protest last December.
The 21-year-old appeared at the hearing at Kingston Crown Court on Friday morning with his parents, who watched proceedings from the public gallery.
He had previously admitted to violent disorder during a protest against increases to university tuition fees at London's Trafalgar Square and Parliament Square.
The court heard that that Gilmour boasted "We're going to break all the laws" at the beginning of an "intoxicated" day of rioting and vandalising property in London.
He was accused of being part of a mob that attacked the a royal convoy containing Prince Charles and Camilla, and hurling a bin at a Jaguar carrying royal protection officers, a charge he denies.
His barrister, David Spens QC, asked allowances to be made: "His memory is likely to be somewhat patchy given his obvious intoxication".
"The weight of the evidence is he is not exhibiting real violence."
Gilmour, who is said to have taken hallucinogenic drugs hours before the protest, was also accused of attacking the front window of Topshop's flagship store in Oxford Street and making off with the leg of a mannequin. He posed sitting on the bonnet of the Jaguar and was also pictured piling newspapers outside the Supreme Court and attempting to set them on fire to them with a cigarette lighter.
He was memorably photographed hanging from a Union flag on the Cenotaph, an act for which he issued an apology the following day. He described the incident at the Cenotaph as a "moment of idiocy", adding that he did not realise that the monument commemorated Britain's war dead.
Gilmour covered his face with his hands and smiled in embarrassment as the court watched footage of his antics. At one point on Thursday, as he sat in the dock, he nervously took his own pulse.
Gilmour, whose biological father is poet Heathcote Williams, is a former model but currently an undergraduate at Girton college, Cambridge. He arrived in court with a noticeably tidier haircut than on his previous public outing, looking pale and sheepish.
He seemed keen to put his history degree to good use in interviews he gave during the protest, telling a BBC camera crew:
"It's like a return to the f**king eighties. It's almost even a return to '68, even more than that. It's like 1789, the French Revolution. Everyone got kettled there, man."
Warming to his historical theme, he was seen shouting at police: "Let them eat cake, they said, but we won't eat cake. We'll eat fire and ice and destruction because we're angry!".