Senior Regional Correspondent

Let’s start by clearing up why he wore the sunglasses.

Sulaimon Brown told me he looked “tired around the eyes” because he’d missed sleep while preparing for his long-awaited appearance Monday before the D.C. Council. The former fringe mayoral candidate hid behind the shades so his fatigue wouldn’t show on television and in photos.

Unfortunately for the dignity of the proceedings and his own reputation, Brown couldn’t also conceal his manic personality. His repeated outbursts — which included using the f-word in sworn testimony and suggesting Council member David A. Catania (I-At Large) was a racist — dominated news coverage of the session.

Council members aggravated the unbecoming atmosphere by swapping gratuitous insults with their excitable witness.

But let’s set aside the theatrics and focus on what’s ultimately important: Do we believe Brown’s claims that the campaign of now-Mayor Vincent C. Gray promised him a job and paid him money in a secret, corrupt deal in last year’s race so Brown would hammer their common opponent, incumbent Adrian M. Fenty?

I have concluded the answer is yes.

Between conniptions at the council hearing, Brown offered specific, detailed answers. He brought no lawyer and often referred to notes to refresh his memory.

More important, we’re not relying on his word alone. We now have physical evidence of payments, in the form of money orders that Brown said he received from Gray campaign aide Howard Brooks. The Post independently connected the orders to addresses linked to Brooks’s family.

Earlier testimony established that top Gray deputies were determined to find Brown a good-paying job in the new administration, despite their concerns over his erratic behavior. The only plausible explanation is Brown’s own description that the Gray campaign had promised him a position.

My confidence in Brown’s account comes with a major caveat, however. It hasn’t been established that Gray himself endorsed any sordid dealings between his campaign aides and Brown.

There’s neither physical evidence nor witnesses’ testimony that the mayor was aware either of any payments, or of any promise of a job. The mayor has maintained from the start that Brown was guaranteed only a job interview.

So it’s conceivable that Gray’s aides orchestrated sleaze behind his back. The two key players fingered by Brown are Lorraine Green, Gray’s campaign chairwoman and close friend, and Howard Brooks. Both have denied wrongdoing, but Brooks’s refusal to testify before the Council, citing the Fifth Amendment, has made him the Mystery Man in the whole affair.

As a result, a version of the classic Watergate question promises to become central to this scandal: “What did the mayor know, and when did he know it?”

That query is already starting to tie Gray in a knot. The mayor doesn’t want to appear to be laying the groundwork to shift the blame to Green and Brooks. But that’s what he’s doing, albeit subtly.

The strategy was evident at the mayor’s news conference Tuesday. Gray opened it with a short, forceful statement in which he said there was “no merit to the allegations made in yesterday’s hearing.” That seemed to be a blanket denial of what Sulaimon Brown had said.

Afterward, though, in a short interview with me, Gray clarified that his denial applied only to what Brown had said about the mayor’s direct, personal involvement.

“There’s no way I can speak for other people. I can’t do that. I want to be clear. I was talking about the stuff he said about me,” Gray said.

So, did the mayor think Green and Brooks might have gone behind his back in dealing with Brown? Gray said he found it “incredible” — but he wouldn’t rule it out.

Later the mayor phoned me to emphasize that his statement “in no way suggests I’m casting aspersions or making suggestions about anybody else.” At the same time, he reiterated that he could only be certain of his own conduct.

Such nuanced comments mean Gray himself is leaving open the possibility that his campaign had a corrupt agreement with Sulaimon Brown. The mayor insists only that he personally had nothing to do with it.

The biggest unknown now is what U.S. Attorney Ronald C. Machen Jr. makes of all this. He is said to have a strong interest in prosecuting public corruption cases, but it would be rather risky to go to trial with Sulaimon Brown as a main witness. Based on Brown’s performance Monday, it would take about 10 minutes of aggressive cross-examination to provoke paroxysms that would demolish his credibility.

Even if the case never makes it to a court of law, however, we can make judgments in the court of public opinion. In that arena, the burden of proof — or, in this case, disproof — rests squarely on the Gray campaign. And it’s getting pretty close to the mayor himself.

I discuss local issues Friday at 8:51 a.m. on WAMU (88.5 FM).