The only reason you see placards in Parliament Square today is because the anti-war protester Brian Haw's demonstration preceded the introduction of the act, which is not retrospective.
Even as Mr Berlusconi rose to address the European parliament, seven Green MEPs protested, raising placards reading: "Everybody is equal under the law" - in reference to concerns that the Italian leader used his political influence to sidestep legal action over his business dealings.
Then they commandeered the necessary materials and a marker pen to create bright placards bearing slogans about Sir Philip and his tax responsibilities – material too libellous to repeat here.
"He talked about doing a deal with the devil and it reminded me of the placards he stood in front of which said 'ditch the witch'," Milne told Guardian Australia.
Many of those who did attend carried home-made placards.
Edward Albee recalls a demonstration they attended during the sixties: "It was a time when Arthur and I were both carrying placards, protesting outside the Soviet Mission to the United Nations," he said.
Organizers supplied placards reading "Stop Watching _____", allowing protesters to fill in their own name – or other slogans and occasional profanities.
And protected behind a privacy screen, four Lib Dem workers stoically continued working away on their campaign, as scores of raucous SNP supporters, their saltires, SNP placards and balloons above their heads, greeted Sturgeon's arrival.
The site owned by Sanderson's uncle and aunt is near Roseacre, and as you wind down the pot-holed lanes towards it, past the huge communication masts of the Royal Navy's Inskip site, placards of opposition appear: "Don't frack with Fylde", "Health not wealth" and "What price fracking?
The narrowness of the street that runs in front of his Roman palazzo forced most of the TV teams to record it all with a foreshortened perspective that gave the impression of a forest of banners and placards.
An aide at his side held his cigarette during doorstep visits and carried "souvenir" Ukip placards that Farage autographed for residents to display in their windows.
