Twenty-year-old Bashir's second disputed victory threatens to damage the reputation of the Union, whose past presidents include a roll call of Prime Ministers such as Gladstone, Edward Heath and Benazir Bhutto of Pakistan.
Bashir was elected president last term but was disqualified. Last week she was elected again by a single vote, but that result was in the balance March 9 as a tribunal met to review charges of malpractice brought against her.
Her friends say that she is the victim of a powerful clique which is determined to prevent an outsider from gaining the post.
Bashir, a native of Yorkshire, last term beat Georgina Costa by 790 votes to 601, but was disqualified on a technicality after she was accused of scrawling some comments on her opponent's election manifesto. It was the first time in the society's history that the results of the election had been overturned.
This time, Bashir beat the society's librarian James Forsyth by 614 votes to 613. But she again faced accusations of malpractice. A third candidate, Matthew Richardson, had used a hidden camera to film his rivals in their colleges on polling day. While both Bashir and Forsyth were alleged to have contravened the ban on active soliciting of votes, only Bashir was accused of breaking the rules.