The District’s chief administrative law judge allegedly steered a $43,000 city contract to the husband of a business partner, hired that business partner into a city job and lied to investigators probing the actions, the city ethics board charged Thursday.

The Board of Ethics and Government Accountability alleged 19 counts of wrongdoing against Mary Oates Walker, the chief judge and top official of the D.C. Office of Administrative Hearings.

The board also levied 10 counts against Kiyo Oden Tyson, the agency’s general counsel, whom Walker hired in 2010 and who is also Walker’s partner in a ­property-management business.

Lawyers for both women denied the allegations Thursday.

According to the allegations, Walker “actively sought” to have a 2011 city contract awarded to Tyson’s future husband. The contract, to move furniture to the agency’s new offices, was worth $43,000.

The board also charged that Walker benefited financially from hiring Tyson because Tyson’s public salary could allow her to invest in property that the two jointly own through their property-management business. As a result, the board charged, hiring Tyson violated conflict-of-interest rules and constituted the use of public office for private gain.

Potentially more serious are the board’s charges that Walker and Tyson made “material misrepresentations” to ethics investigators and obstructed the investigation, Board Chairman Robert J. Spagnoletti said.

Among other misrepresentations, Walker allegedly minimized Tyson’s role in operating the property-management business, even though investigators had bank records indicating otherwise, according to the board.

Barring a settlement, the case will be tried this spring by the ethics board, an independent panel with the power to levy significant fines. An adverse finding could also result in job sanctions for Walker and Tyson. It was unclear whether the matter would be referred to prosecutors for criminal investigation.

Administrative law judges handle a variety of disputes involving government agencies, ranging from license and permit decisions to trash violations to welfare-eligibility rulings and rental-housing appeals.

James F. Hibey, an attorney for Walker, called the charges an “outrageous abuse of process” and questioned whether the ethics board has jurisdiction over the Office of Administrative Hearings.

“I can tell you that the allegations of misconduct are demonstrably false,” he said. “We will fight the charges vigorously and in doing so expose the real wrong­doers. Chief Judge Walker is the victim of scurrilous lies and backroom politics, all of which will be exposed as the now-public process proceeds.”

Tyson’s attorney, Billy Martin, said his client also denies the charges. “We don’t believe the allegations are supported by the evidence, and we also have grave concerns about Ms. Tyson’s ability to receive due process before the board,” he said. Martin, like Hibey, questioned whether the ethics board has jurisdiction over the agency, which is independent of the mayor and the bulk of the city government.

Walker has, for much of her tenure, been locked in a heated workplace battle with a number of her fellow judges. The ­charges unveiled Thursday added new fuel to that conflict, alleging that Walker “harassed or retaliated against employees acting in good faith” by reporting potential wrong­doing.

In June 2012, 15 of the 24 judges in the Office of Administrative Hearings signed a letter accusing Walker, the office’s top executive, of a “lack of transparency, predictability, and competence.” It was an unusual gesture of no confidence that was sent to Mayor Vincent C. Gray (D) and D.C. Council Chairman Phil Mendelson (D).

Walker responded at the time by characterizing those judges as disgruntled with management ­changes she had imposed to improve the agency’s operations. “These ­changes have been unpopular, especially with employees who, for years, received pay and benefits with little accountability,” read a statement she released.

The judges’ letter came shortly after WJLA-TV aired a report questioning the moving contract awarded to the company owned by Tyson’s husband.

After receiving the judges’ letter, Gray referred the contract matter to the District’s inspector general, Charles J. Willoughby.

Unlike the ethics board, Willoughby’s office did not recommend action against Walker or Tyson. Willoughby’s office concluded that Walker should have disclosed her relationship to the moving contractor but found no evidence that she improperly pressured procurement officials to award the contract.

“The preferred action may have been for [Walker] to disclose her knowledge of the relationship,” Willoughby wrote in a letter to Gray in May. But investigators “found an insufficient basis to conclude the existence of misconduct on her part under the circumstances.”

The letter was never publicly circulated by Willoughby’s office. A redacted copy was obtained by The Washington Post last year through a Freedom of Information Act request.

About a month after sending their letter objecting to Walker, the rank-and-file judges in the office filed papers seeking to form a union. Walker has fought their attempt to organize, hiring an outside law firm to litigate the matter even after the District’s attorney general withdrew. The organizers recently prevailed in a key ruling, but the matter remains in the hands of a city labor board.

Several of the junior judges and union organizers attended the ethics board’s meeting Thursday. “It’s a tremendous vindication for the judges,” said Paul Shearon, secretary-treasurer of the International Federation of Professional and Technical Engineers, the union backing the organizing drive.

It was unclear whether Walker and Tyson will remain on the job. Pedro Ribeiro, a spokesman for Gray, said that the “allegations are immensely disturbing” and that the mayor’s office is reviewing the charging papers.

Walker was appointed chief judge in 2010 by Gray’s predecessor, Mayor Adrian M. Fenty, and her six-year term is set to end in February 2016.She is a graduate of the Howard University School of Law and a former labor counsel for the Hershey Co.