EVER SINCE troubling allegations surfaced about events in the 2010 election campaign and early administration of D.C. Mayor Vincent C. Gray (D), we have repeatedly urged him to provide a full disclosure of events.

Clear the air,” we wrote in 2011. “Come clean,” we said last week.

Mr. Gray, following the advice of the attorney representing him amid a federal investigation, has largely stayed silent. He has denied he did anything wrong, but he also has refused to go into any detail about his activities or his knowledge of events. He has declined several requests to meet with prosecutors.

And so, as people associated with his 2010 campaign have pleaded guilty to federal charges in what the U.S. attorney called an election “corrupted by a massive infusion of cash that was illegally concealed,” the questions have mounted and Mr. Gray’s silence has become more and more untenable.

Should Mr. Gray run for reelection — a decision he is pondering — even he recognizes the need to provide some answers. “I think there are questions that, you know, will be asked. . . . And we’ll be prepared,” Mr. Gray told NBC4 reporter Tom Sherwood during a recent appearance on WAMU’s “The Politics Hour.”

It’s useful, then, to detail just a few of the questions that Mr. Gray will have to address. We started by asking Mr. Sherwood what he would have asked had the mayor been willing to entertain questions.

“Your long-time friends — Vernon Hawkins and Jeanne Clarke Harris and several others — have all pleaded guilty to illegal actions on your campaign’s behalf. Why do you think they all thought it was all right to violate the law on your behalf? And who is supposed to be minding the store if not you?” Mr. Sherwood e-mailed us. Prosecutors have detailed a scheme in which $653,800 from a businessman with significant city government contracts was funneled through Ms. Harris to fund a separate get-out-the-vote effort on behalf of Mr. Gray and managed by Mr. Hawkins for the September 2010 Democratic primary.

We would like to know when and how Mr. Gray learned of this secret and illegal shadow campaign. Is a former campaign worker correct in saying that he questioned Mr. Gray about the source of funding for Mr. Hawkins’s field operations in the summer of 2010? Mr. Gray, The Post’s Nikita Stewart has reported, met in spring 2010 at Ms. Harris’s apartment with Jeffrey E. Thompson, the city contractor who is alleged to have financed the shadow campaign but who has not been charged. What did Mr. Gray and Mr. Thompson discuss? And, when they met again after Mr. Gray’s election, what was on the agenda? Did they discuss Mr. Thompson’s lucrative contracts with the city?

After Ms. Harris pleaded guilty, Mr. Gray allowed that “this is not the campaign we intended to run.” But the mayor has built a career on attention to detail. Why didn’t he know what his close associates were doing?

Still unanswered are questions about Mr. Gray’s dealings with Sulaimon Brown , the fringe mayoral candidate whose allegations led to the federal probe. Mr. Brown said he was promised a city job in exchange for staying in the 2010 Democratic primary to attack then- Mayor Adrian M. Fenty (D). Mr. Brown’s allegations of getting cash from the Gray campaign have been substantiated by people pleading guilty to federal charges . So why shouldn’t Mr. Brown be believed when he says that Mr. Gray knew about and approved the deal? Is it plausible that Mr. Gray was referring, as he has insisted, to only the promise of a job interview when he texted Mr. Brown after the election that “We did not renege on any commitments to you?”

Whether or not Mr. Gray seeks a second term — and however the ongoing federal investigation into his campaign ends — he owes D.C. citizens an explanation. Not to mention an apology.