Washington ? A senator Friday requested that a Minneapolis FBI agent testify next week on Capitol Hill as Congress delves into the bureau’s activity before Sept. 11.

Sen. Charles Grassley, R-Iowa, said FBI agent Coleen Rowley could help the Senate Judiciary Committee improve FBI operations by appearing Thursday. Grassley also said Rowley could help restore public confidence in the bureau.

Rowley wrote a letter criticizing FBI headquarters for refusing to allow Minneapolis FBI agents to step up their investigation of Zacarias Moussaoui, who was in custody in the weeks leading up to Sept. 11.

Now under indictment, Moussaoui is accused by the government of being a conspirator in the Sept. 11 attacks. The FBI was suspicious of his flying lessons last August and he was picked up on an immigration violation.

Rowley has pledged not to discuss the Moussaoui case, so Grassley said national security concerns should not stand in the way of her testifying.

Minneapolis FBI spokesman Paul McCabe declined to comment on Grassley’s request.

The office of Sen. Patrick Leahy, D-Vt., the judiciary committee chairman, will determine whether to call Rowley as a witness.