WASHINGTON (AP) — The chairman of the House Oversight Committee issued a subpoena Friday for an IRS official to testify at a hearing on the Freedom of Information Act.

Rep. Jason Chaffetz, R-Utah, said he issued the subpoena after the IRS declined to provide the official who oversees information requests. Instead, the IRS offered to have IRS Commissioner John Koskinen testify.

In a letter to Koskinen, Chaffetz said he wanted to hear from the agency's expert on responding to information requests. Chaffetz issued the subpoena for Mary Howard, the IRS director of privacy, governmental liaison and disclosure. She reports to a deputy commissioner.

The IRS said Friday it will send Howard to the hearing, which is scheduled for Wednesday. Officials from several government agencies are scheduled to testify.

"In order to conduct effective oversight we must hear from the individuals with the greatest insight into the issues we are exploring," Chaffetz said in a statement. "When an agency attempts to undermine the role of Congress by refusing to allow a witness to testify, issuing a subpoena is not only necessary but appropriate."

The IRS said in a statement that the commissioner repeatedly offered to testify. The agency said Koskinen is the most appropriate witness because the hearing will cover issues that go beyond the scope of one office.

"It's unfortunate the committee insisted on taking the formal step of issuing a subpoena to compel the appearance of a career civil servant," the IRS said in its statement. "The IRS will participate in the hearing as it always intended, and it will continue to cooperate with this important oversight group."

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