The Court of Cassation said Wednesday the sex in the rape case had to be consensual because the victim was wearing jeans at the time. They said it is impossible to remove tight pants like jeans "without the cooperation of the person wearing them."
The ruling has enraged female lawmakers, prompting them to call on women all over Italy to join a "skirt strike" and wear jeans.
"If we go on like this, every woman that doesn't wear a chastity belt will have the 'right' to be raped," said Sonia Viale of Parliament's equal opportunities commission.
The decision overturned the 1998 conviction of Carmine Cristiano, a 45-year-old driving instructor in southern Italy, for raping an 18-year-old student.
A lower court had sentenced Cristiano to two years and eight months in prison, but the appeals court said the girl must have consented to sex and sent the case back for retrial.
The court also questioned why the victim, identified only as Rosa, waited several hours to tell her parents she'd been attacked.
"It could be seen as a manual for aspiring rapists,"the Rome daily Il Messaggero fumed in a front-page story.
"Jeans: An alibi for rape," read a sign held up in Parliament by five jeans-clad lawmakers.
Alessandra Mussolini, a deputy of the rightist National Alliance, who led Thursday's protest, called the ruling "shameful." She said it "offends the dignity of women."
"Women are already scared of reporting rapes, this just makes it worse," she said.
Massimo D'Alema said he could not comment on the ruling in his role as prime minister. But as a private citizen he expressed his "solidarity" with the female lawmakers.
A federation of housewives ridiculed the court by offering a prize to any designer who comes up with "easy-off jeans." It also planned a march in dungarees to the Justice Ministry.
Although many were upset at the ruling, Federica Snider, a 17-year-old in Rome, agreed with the three-judge panel. "It's impossible to rape someone wearing jeans. You've got to really overpower them," she said.
The ruling drew attention to the makeup of the appeals court, which has 10 female justices and 410 men.
"Nothing can be done. Justice in the court is in the hands of men, often elderly, with old ideas," a veteran female justice, Simonetta Sotgiu, told the newspaper La Repubblica.
She denounced the ruling as setting a dangerous precedent. "It paves the way for the rape of women in jeans," she said.