Fewer people were in attendance, but the cause was worthier and the range of celebrities - from veteran playwright Arthur Miller to Hollywood superstarlet Gwyneth Paltrow - more impressive. At an Amnesty International ceremony to reward people in the arts and media, Bianca, who falls somewhere between the two categories, received the prize for "Leadership", the human rights equivalent of an Oscar for best actor.
Promiscuous in her choice of causes as her ex-husband is in his choice of women, Bianca has reinvented herself as a campaigner for justice in Bosnia, the Brazilian Amazon, Central America, Tibet and as an anti- death penalty activist in the US.Combining beauty and celebrity with a passion for good works, she set the note for an Amnesty event that was oddly reminiscent of Oscar night in form, if solemn in content. There were video clips of the poor and suffering in Africa and Asia, of Nelson Mandela and of Bianca in Bosnia. Suzanne Vega sang of abused women and children.
In Britain, where people cannot help but see the funny side of things, such an event, to succeed, has to feature something of the spirit of John Cleese and the Secret Policeman's Ball. In the US people struggle to reconcile high-mindedness with humour so, when the subject is serious, they shrink from comedy for fear of being misconstrued.
Arthur Miller, who received an award for The Crucible, his play about the politics of paranoia, may have been puzzled upon discovering that one of his fellow honorees for the evening was the executive producer of Star Trek. Matthew Modine, the Hollywood actor, did the introductions, describing the TV series as "a source of inspiration and understanding for millions". The programme explained that Star Trek had received a "Special Achievement" award because of its "belief in the human race's ability to triumph over greed, aggression and prejudice". The moment screamed for a light crack but none was forthcoming.
Star Trek, it turned out, was the night's big winner. Patrick Stewart, the actor best known for playing the USS Enterprise's Captain Jean-Luc Picard, received an award for "Inspiration". A forceful voice on humanitarian matters who funds an Amnesty scholarship programme, Stewart was in no mood for jokes either. He described Amnesty as a bodythat "speaks for those who cannot speak for themselves" and "tells oppressors: `We know who you are and what you're doing!'"
Another unlikely British award winner at this most American of ceremonies was Glenda Bailey, the pleasingly unassuming editor of Marie Claire magazine. Gwyneth Paltrow introduced her, having been first introduced by her mother and the actress Blythe Danner. Ms Paltrow, an uncannily convincing Emma in the film of Jane Austen's book, seemed girlishly diffident in real life. Ms Bailey was receiving her award, Ms Paltrow awkwardly explained, because of the brave stand she had taken in defence of international women's rights.
Glancing at the latest issue of Marie Claire, it was not clear what the Amnesty awards panel had in mind. "The Sex You Want and How to Get it", the front cover shrieked. Lower down, the words "Special Report: Where Rape is a Woman's Fate" unravelled the mystery. The story was about women battered by India's caste system. Previously Marie Claire had run a story about Pakistani women who are raped and then sent to jail. Ms Bailey declared, sincerely, that she felthumbled by her award. As Ms Jagger explained later, Ms Bailey's award was richly deserved because she made a point of reaching out to readers whose consciousness of matters of justice would otherwise remain dim.
Ms Jagger herself appealed for an investigation into the massacre at Srebrenica and stood up to those detractors who say she has no right to meddle. "To speak out for human rights is not easy for a celebrity to do, but knowing what is right and wrong - knowing what justice is - does not require you to be an expert."
She left the stage to a warm ovation and the satisfaction of sensing that her quest to be recognised as a mature woman in her own right, and not just the ex-wife of an ageing rocker, was finally coming to an end.