Dame Helen Mirren has found herself at the centre of a prizegiving controversy after three judges from the London Evening Standard Theatre Awards quit amid allegations of vote fixing to secure the movie star a top honour.

Last month (Nov13), the 68 year old picked up the accolade for Best Actress for her portrayal of The Queen in West End stage play The Audience, but now the legitimacy of her win has come under scrutiny.

According to reports, Mirren was tied with another actress for the award at the end of a secret ballot, but one judge, Evening Standard newspaper writer Henry Hitchings, went on to change his vote, giving the Oscar winner the edge over her closest rival. The identity of the Best Actress runner up has not been revealed, but the category featured competition from Kristin Scott Thomas, Linda Bassett, Billie Piper and Lesley Manville.

News of Hitchings' last minute vote change has since prompted three of the seven judges to leave the seven-strong panel - theatre critics Charles Spencer, Georgina Brown and Susannah Clapp have all stepped down and will not return for next year's (14) awards show.

In a blog post for Britain's The Telegraph, Spencer claimed his "jaw dropped" when Mirren was announced as the Best Actress winner at the London ceremony, adding, "In the end awards are no more than the icing on the theatrical cake. But this year it left a bitter taste in the mouth."

However, Theatre Awards judge and Evening Standard editor Sarah Sands has dismissed the accusations, insisting there was nothing wrong with Hitchings' change of heart because his initial vote concerned The Light Princess actress Rosalie Craig, who had been removed from the Best Actress category in favour of inclusion in the Best Musical Performance shortlist.

She says, "(It was) an absolutely legitimate choice. It would be absolutely wrong to suggest that there was anything untoward about the (voting) process."