Pakistan President Asif Ali Zardari, presumed to be one of the nation's richest men, did not file tax returns last year, a new report contends. Neither did Interior Minister Rehman Malik. And nearly 70 percent of the members of Parliament failed to pay taxes, according to what may be the first comprehensive, independent review of major politicians' tax returns (or lack thereof).

The report, published earlier this month by the Center for Investigative Reporting and the Center for Peace and Development Initiatives, has not only caused consternation among the political elite but also raised further questions about Pakistan's ability to meet its domestic revenue obligations and cover foreign debts.

Zardari's spokesman told the media that the president had indeed filed a return — after initially claiming he was exempt.