Charlie Gilmour, son of Pink Floyd guitarist David Gilmour, has lost his High Court appeal to cut the 16-month prison sentence handed to him after he went on a drug-fuelled rampage at last year's student protests.
The 21-year-old from Billingshurst, West Sussex, was seen hanging from a union flag on the Cenotaph and leaping onto the bonnet of a car that formed part of the royal convoy during the protests last December.
Despite being a history student at Cambridge University, Charlie Gilmour claimed he did not realise he was swinging from the historical monument.
Judges previously heard the student was "aware there was a Cenotaph" but did not know the "monument from which he was swinging was a war memorial - let alone the Cenotaph".
Charlie Gilmour had admitted violent disorder after joining the thousands protesting against tuition fees and was jailed last July.
During the protest, 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!".