For the third time in six months, Senator Robert Menendez stood before a judge in Manhattan on Monday to be arraigned on new criminal charges filed as part of an expansive federal bribery investigation.
Mr. Menendez, a Democrat from New Jersey, has previously pleaded not guilty to accepting bribes and acting as an unregistered agent of a foreign government.
On Monday, he pleaded not guilty to obstruction of justice, a charge added last week in an updated indictment against the senator; his wife, Nadine Menendez; and two New Jersey businessmen, Wael Hana and Fred Daibes.
The new charges come less than two months before the scheduled start of the trial, May 6.
The obstruction of justice charge appears to be related to information provided by Jose Uribe, a former insurance broker charged in September in the bribery conspiracy. Earlier this month, Mr. Uribe, 56, admitted that he had tried to bribe the senator with a $60,000 Mercedes-Benz convertible in exchange for Mr. Menendez’s efforts to scuttle an insurance fraud investigation in New Jersey.
Mr. Uribe also agreed to cooperate with prosecutors.
Mr. Uribe told the judge, Sidney H. Stein of Federal District Court, that he and Ms. Menendez met at a Marriott hotel to get their stories straight soon after he received a subpoena. He said he had agreed to lie to investigators — and to his own lawyer.
Last week’s updated indictment accused the senator and his wife of lying to their lawyers, too, and trying to make it appear as though car payments arranged by Mr. Uribe were loans, not bribes.
