Louisiana politicos and their corporate backers blew it out last weekend at their annual Washington Mardi Gras bash. This week, some are nursing ethical hangovers.

Organizers of the event, including aides to Cajun lawmakers, are trying to determine how different portions of the event square with tightened ethics rules.

They said the ethics committees gave their blessing to this year’s celebration, held as usual at the Hilton Washington. But evolving interpretations of the new standards are sowing confusion about how, precisely, private interests can be involved as sponsors in future years.

“The question for the delegation is with the new rules coming forth, is past ethics committee guidance still accurate?” said one staffer for a Pelican State lawmaker. “We’re continuing to decompress and we’ll revisit this in a couple weeks.”

Chiefs of staff to GOP Reps. Jim McCrery, Charles Boustany and Rodney Alexander and Democratic Rep. Charlie Melancon huddled Tuesday to discuss the issue.

“We wanted to make sure we’re all OK and that we all have the same comfort level. Some people do think differently about how these events are organized,” said one person familiar with the chiefs-of-staff meeting.

One aide said staffers for the lawmakers are likely to approach the Committee on Standards of Officials Conduct in coming weeks to clarify lingering uncertainties left over from its guidance.

There appear to be two primary points of doubt in the mechanics of last week’s event: the distribution of corporate-bought tickets to Members of Congress and staff, and parties that lawmakers throw in hotel suites for which private interests often pick up the tab.

Lawyers for Louisiana Alive, the group that organized the festivities’ kickoff party a week ago Thursday, asked both the House and Senate ethics committees whether corporate interests and lobbying firms could buy packages of tickets for the evening and then hand them back to the nonprofit with lists of Congressional operatives to invite.

That approach was considered kosher under old rules, allowing lobbyists a way to pay for tickets to charity events that would otherwise shatter the $50 gift limit.

But this year, ethics panels have split on the question. The Senate committee is still considering whether to endorse the tactic, while the House said it is still OK, according to Tim Jenkins, a lawyer for O’Connor & Hannan who consulted the committees for Louisiana Alive.

Consequently, Louisiana Alive held off giving tickets to Senators and their staff, said Wayne Smith, a lobbyist who heads the group.

Their counterparts across the Rotunda, meanwhile, enjoyed free admission courtesy of sponsors including the American Farm Bureau, Blank Rome Government Relations, Duke Energy, Lockheed Martin, Southern Co. and the Wine and Spirits Wholesalers of America.

Revelers have to pay their own way on the following nights — to a black-tie dinner on Friday and gala on Saturday. But those looking for a break from the ballroom action, or a late-night scene after the official events have ended, head upstairs to suites reserved for every lawmaker in the state’s delegation.

The rooms offer food and drinks, and sometimes more, participants said. McCrery has been known to have live music. Then-Rep. Billy Tauzin held mass in his room on Saturday afternoon, for those flying home on Sunday.

This year, only Rep. Richard Baker (R) paid for his own suite, said an aide to another member of the Louisiana delegation.

Aides said others were paid for by “mini-krewes” — subsets of the Mystick Krewe, the organization that sponsors the official activities on Friday and Saturday — or by corporate backers.

For example, Rep. William Jefferson (D) had his suite covered by Liberty Bank & Trust, a New Orleans outfit, said his spokeswoman Ashley Wilson.

Costs for the parties range widely. In 2005, when Jefferson paid for his own event, it totaled $2,497, according to campaign finance reports. But last year, then-Rep. Bobby Jindal (R) shelled out $8,327 for his, campaign finance records show.

So far, the parties have passed ethics committee muster by meeting the qualifications of a widely attended event: More than 25 people from a diverse background cycle through, and since nearly all are constituents, lawmakers and staff can reasonably assert the revelry relates to their official duties.

Still, staffers want a more clear-cut thumbs up from the ethics committees before repeating the parties next year. “They didn’t really address that fully in their last letter,” one House aide said of the ethics panel. “That’s one of the questions we’re trying to figure out. Are we truly in a gray area, or is it more white or black?”