Thompson, in 2010 (C-SPAN)

The contract to develop a new property tax system, worth as much as $8 million over two-and-a-half years, was unexpectedly canceled by the Office of the Chief Financial Officer on Thursday.

According to an official with knowledge of the matter, Thompson’s firm — Thompson, Cobb, Bazilio & Associates — won the bidding process but the award had not yet been forwarded to the D.C. Council for approval.

A letter to bidders dated Friday reads that “in the best interests of the District,” the agency “determined that a complete review of the requirements is necessary as specifications have been found to be inadequate and in need of revision.”

David Umansky, a spokesman for Chief Financial Officer Natwar M. Gandhi, said the cancellation was not related to the ongoing investigation.

“In the time it has taken, the technology has improved,” he said. “The IT people and the tax people have decided they don’t have to do it that way, which is more expensive.”

The solicitation has been delayed, and Umansky said it was unclear if a new request for proposals would be offered or the project would be included as part of another contract. The new tax system is expected to replace an old system that, in a prior incarnation, was used by OCFO fraudster Harriette Walters to steal nearly $50 million in city funds.

The cancellation saves the D.C. Council from having to take a supremely uncomfortable vote on a Thompson-related contract. At least four members have had their past campaigns served with subpoenas seeking information on Thompson and his associates.

TCBA continues to do other business with the city: OCFO paid the firm $998,128.44 on Feb. 7, pursuant to a contract to evaluate and verify software related to the District’s basic accounting system. That amount is just below the $1 million threshold requiring council approval.

The firm also holds a contract dating to 2010 to audit records in the District’s unemployment insurance office. That contract has been worth about $665,000 to date.

TCBA’s president and chief operating officer, Ralph B. Bazilio, wrote in a March 5 letter that a raid of its offices days earlier was related to “campaign fundraising events” hosted by Thompson and that the firm was cooperating with authorities. Bazilio did not return a call for comment Thursday.

Thompson’s attorney, Brendan V. Sullivan Jr., has declined to comment.