Federal prosecutors have accused a D.C. businessman at the center of a far-reaching corruption probe into Mayor Vincent C. Gray’s 2010 campaign of obstructing their investigation, according to a court order unsealed Monday.

The year-old ruling by U.S. District Judge Royce C. Lamberth also criticizes Jeffrey E. Thompson for engaging in a protracted legal battle over millions of pages of personal and business records seized from his home and offices last March.

In the ruling, Lamberth said that prosecutors argued against delaying review of the records “because of efforts by Thompson to obstruct the investigation.”

Thompson, who is alleged to have financed a “shadow campaign” for Gray, has fought to keep the U.S. Attorney’s Office from reviewing some of the documents. Last May, Lamberth rejected Thompson’s effort to temporarily block the review, writing that it would “grind the government’s efforts to a halt.”

Thompson’s legal challenges “consume institutional resources that could be better spent on conducting the underlying investigation,” Lamberth wrote in the redacted ruling.

“The government has the right to review those documents on a prompt basis, and the public has the right to see alleged wrongdoers swiftly brought to trial.”

While most of the opinion does not identify Thompson by name, there is one reference to “Thompson” and it is clear that Lamberth is referring to the investigation.

In March, a panel of the U.S. Court of Appeals for the District of Columbia Circuit sided with the government, ruling that prosecutors could set up an independent filtering team to review the records that might contain privileged information. The federal appeals court rejected Thompson’s request last week for review by the entire court.

But the documents remain in legal limbo because Thompson has the option to appeal to the Supreme Court.

Thompson’s attorney, Brendan V. Sullivan Jr., does not generally comment on his cases and did not return a phone message Monday.

Staff writer Mike DeBonis contributed to this report.