"If you release them you tell a story," she said. "If you don't release them you leave it up to the imagination of anybody who wants to talk about it to talk about it."
But she reacted testily when asked whether she and members of Congress should abide by such rules.
"There are no rules. There are no rules. There's no rule about releasing his tax return, so what rules are you referring to?" she asked, growing clearly frustrated. Asked about the standard she had cited for a presidential candidate, Pelosi said: "It's up to the American people. The American people are the judges of that."
After being questioned about why her demand for more transparency from Romney shouldn't apply to Congress as well, she briefly changed course and said the issue of tax returns was not important.
"The tradition that was honored by this same person's father," Pelosi said, recalling how George Romney released several years of his tax returns when he ran for president in 1968. "Now I'm not here, this is not important to me, let me say this: What's important to me are jobs and the rest," Pelosi said.
Speaker John Boehner, R-Ohio, had a terse response. "I've never released my tax returns. That's my private business, just like it's your own private business," he told a news conference.
Boehner called the furor over returns a "sideshow ... the American people are asking the question where are the jobs. They're not asking where are the tax returns."
Over the last three months, McClatchy asked all members of Congress to provide their tax data. Seventeen gave their returns, or provided similar documentation of their tax liabilities. Nineteen including Pelosi would not disclose returns. Most did not respond.
Moves were afoot Thursday to increase disclosure, but not necessarily for members of Congress. Rep. Sander Levin of Michigan, the top Democrat on the tax-writing House Ways and Means Committee, is preparing legislation requiring presidential candidates to disclose 10 years of returns. He is studying whether to include members of Congress and congressional candidates. Levin's website features five years of his tax returns.
Lawmakers now must annually file financial disclosure forms, but experts criticize those forms as often being too vague. The forms contain ranges of income, making it difficult to pinpoint someone's worth. And there's no direct information on tax liabilities.