The D.C. Office of Campaign Finance yesterday began investigating whether Mayor Anthony A. Williams's reelection campaign failed to report contributions from the Washington Teachers' Union.

The probe will focus in part on whether the work of Gwendolyn M. Hemphill, who co-chaired Williams's campaign, should have been reported as an in-kind contribution from the union, said Benjamin F. Wilson, chairman of the D.C. Board of Elections and Ethics, which oversees the campaign finance office. Hemphill had a paid job as assistant to the union's president at the time.

Also at issue is the Williams campaign's use of teachers union telephone banks. The campaign did not report use of the phone banks as an in-kind contribution on its financial disclosure reports. A similar arrangement during the mayor's 1998 campaign also was not reported.

"We are not prejudging this situation," Wilson said. "We have a responsibility to conduct an investigation, obtain the facts from the union and individuals involved and at that point . . . make a decision as to appropriate action to be taken."

Mayoral spokesman Tony Bullock said the campaign properly reported all contributions and expenses.

"It's perfectly appropriate for the Office of Campaign Finance to look at the contributions and expenditures of the mayor's campaign," Bullock said. "There's nothing to be surprised about. That's what they're supposed to do. Our filings are comprehensive and detailed and provide all the information that should be provided."

The campaign finance office probe is being conducted independently of a criminal investigation into the alleged improper use of more than $2 million in teachers union money. According to an FBI affidavit, Hemphill, former union president Barbara A. Bullock, former treasurer James O. Baxter II and others used union money to purchase clothing, furs and other luxury items. No charges have been filed in that investigation.

Last night, about 150 members of the teachers union held an unofficial meeting at Dunbar Senior High School in Northwest Washington and issued a vote of no confidence in the union's executive board, interim president and board of trustees.

To shouts of "No confidence!" and pumping fists, all but two of the teachers in the audience voted in support of the measure, which activists said was designed to put additional pressure on the union's embattled leadership. The vote was unofficial because the executive board had refused to sanction the meeting.

The members also launched a drive to secure 800 signatures on a petition to recall the elected leaders.

"I support the no-confidence vote, but I think we should go even further and give a vote of censure," said S.M. Foster, a Dunbar social studies teacher who was in attendance. "I doubt if [the leaders] will listen, but we tried to get our point across."

The teachers union endorsed Williams (D) for reelection, and Barbara Bullock and Hemphill made direct personal contributions to his campaign that were listed in campaign finance reports.

Mayoral spokesman Bullock, who is not related to Barbara Bullock, said Hemphill's work as campaign co-chair was not an in-kind contribution from the union because she worked for the campaign only in the evenings and on weekends. Hemphill's attorney, Frederick D. Cooke Jr., has said that his client put in a full day at the union and volunteered for the campaign in her free time.

Bullock also said there was nothing unusual about the campaign's use of phone banks at union offices.

"Unions very often do phone banking for the candidates they support," Bullock said. "I'm not sure it's possible to put a dollar figure on the use of an organization's phones for a couple of nights."

But Kathy S. Williams, the general counsel for the campaign finance office, said the telephone banks should have been listed as an in-kind contribution if volunteers made the phone calls in cooperation with the mayor's campaign.

Wilson said the campaign finance office also will look into Hemphill's claim that the mayor's chief of staff last year asked her to take care of a bill of about $2,000 for costs associated with D.C. voting rights T-shirts and other items distributed at the Democratic National Convention in 2000. Hemphill has said she used union money to pay the bill.

Kelvin J. Robinson, Williams's chief of staff, has said that he expected the bill would be paid from campaign, not union, funds.

The bill was supposed to be paid jointly by Williams and Del. Eleanor Holmes Norton (D-D.C.). Yesterday, Norton's office released a copy of a letter she sent to Williams on Dec. 14, 2001, seeking payment of his share of the bill to the vendor.

"This company has been waiting over a year now and has not made a big deal of this, but I assure you they will and I think you would find it embarrassing," Norton wrote. "I paid for my share of the costs incurred at the Convention long ago and you agreed to pay other costs. . . . Please ask your finance chair to pay up now."

Norton spokeswoman Doxie McCoy said Norton viewed her share of the costs as a campaign expense and treated it accordingly.

The D.C. campaign finance office also will look into a report that the union sent the mayor's office $5,000 in 2000 to help pay for Christmas parties sponsored by a nonprofit children's organization, Wilson said.

The FBI and the U.S. attorney's office, which are conducting the criminal investigation into the disappearance of teachers union funds, also are looking into the allegations that union money was spent on the D.C. voting rights T-shirts and on the Christmas parties, according to a source familiar with that probe.

Staff writers Spencer S. Hsu, Allan Lengel and David Nakamura contributed to this report.

D.C. teachers emerge from a meeting at Dunbar High School, where about 150 members of the union issued an unofficial vote of no confidence in the leadership.