A diminutive 64-year-old grandmother who refuses to be bound by the rigid constraints imposed on women in Iran proved more than a match for the president of the Islamic Republic yesterday.

Zahra Rahnavard had already broken all precedent by actively campaigning for her husband, Mir Hossein Mousavi, a relative moderate who is President Mahmoud Ahmadinejad’s strongest challenger in Friday’s presidential election. Yesterday, she went a step further by summoning the domestic and international media to a press conference at which she tore into Ahmadinejad for lying, humiliating women, debasing his office and betraying the principles of the revolution.

What sparked her fury was Ahmadinejad’s televised debate with her husband last week in which he challenged Rahnavard’s considerable academic qualifications, suggesting that they were earned not on merit, but through the patronage of a corrupt political elite.

“He wanted to destroy his rival through lies,” she declared in a 90-minute finger-wagging tour de force, and she vowed to sue the president if he did not issue a public apology within 24 hours.

It was a more forceful attack than any of Ahmadinejad’s three male challengers have managed, and would have been remarkable in any election, let alone in male-dominated Iran. It also injected more uncertainty into a race that already has an outcome impossible to call.

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