BRASÍLIA, Dec. 4 — The president of Brazil’s senate, Renan Calheiros, resigned his leadership post to avoid being expelled from Congress by his fellow senators because of a lengthy corruption scandal.
Mr. Calheiros, who has been a key ally to President Luiz Inácio Lula da Silva, became the latest political casualty in a series of corruption investigations that have dogged the president this year.
In resigning his post, Mr. Calheiros, 52, survived a vote by the senators to oust him because of misconduct allegations, by a count of 48 to 29. He continued to deny the allegations in a half-hour speech on the Senate floor late today.
The accusations against Mr. Calheiros, first made by Veja magazine in May, were the most salacious in a year of political scandals in Brazil. They involved using funds from a lobbyist to pay for the child support of a daughter from an extramarital affair with Monica Veloso, a television journalist who leveraged the scandal into an October spread in Brazilian Playboy.
Subsequent inquiries into Mr. Calheiros’s business dealings led to other revelations about income tax fraud and the use of a proxy to buy a stake in a radio station. Mr. Calheiros remained defiant, claiming that his income from a number of farms allowed him to afford the generous contributions on a salary of a little more than $6,000 a month.
In September, the Senate voted by secret ballot against impeaching him, even after the Senate Ethics Committee concluded that he had failed to show enough legitimate income to cover his expenses. Public outrage following that vote forced Congress to eliminate secret ballot votes for ethics violations.
The secret vote sparing Mr. Calheiros came just days after Brazil’s Supreme Court decided that 40 people, including the president’s former chief of staff and several members of Mr. da Silva’s Workers Party, should face charges over an illegal fund-raising scheme to finance election campaigns and bribe members of congress. Mr. da Silva has denied knowing anything about the illegal activities, known as the mensalão, or “votes for cash,” scandal.
In October, Mr. Calheiros took a 45-day leave as president of the Senate. He said today in his resignation letter that he did not resign then because that would have meant accepting “infamy and mistruths.”