What’s the difference between a French kiss in a hallway and paying a French Quarter prostitute for sex? One is a grievous political sin worthy of resigning from Congress and the other is paying a French Quarter prostitute for sex.

Rep. Vance McAllister (R-LA) is now facing resignation calls from within his party, including from Louisiana Gov. Bobby Jindal and the chairman of the Louisiana Republican Party, after being caught on camera smooching a staffer. But while McAllister, who campaigned as a social conservative, is being attacked for hypocrisy, a fellow Louisiana Republican never faced the same opprobrium during his sex scandal.

David Vitter, a two-term senator from the Pelican State and ardent social conservative, admitted to patronizing prostitutes in 2007. The Louisiana lawmaker, while denying links to New Orleans prostitutes, admitted to placing a call to “the DC Madam” while in Congress, saying it was “a very serious sin in my past for which I am, of course, completely responsible.”

“Several years ago,” he added, “I asked for and received forgiveness from God and from my wife in confession and marriage counseling.” Vitter has since been reelected to the Senate and is a heavy favorite to be his party’s gubernatorial nominee in 2015.

The difference between McAllister and Vitter apparently lies not in the nature of the sins but their ties to their party. The freshman congressman was a surprise special election winner in November 2013, after riding the endorsement of cast members of the television show Duck Dynasty to victory. He was an outsider who had never run for office before and upset the establishment candidate, state Sen. Neil Riser.

Vitter is a Harvard grad and former Rhodes Scholar who returned to his native Louisiana to attend law school at Tulane. Three years after graduating law school, he was elected to the state legislature. Considered a rising star in the Louisiana GOP, Vitter made it to Congress just after his 38th birthday, beating former Governor David Treen in a runoff in a 1999 special election. Five years later, Vitter defeated Democrat Chris John, a fellow congressman, to become the first Republican elected to the Senate from Louisiana since Reconstruction.

So when Vitter got into trouble, he was a known quantity who had shown himself to be politically formidable. People owed him favors and he owed them favors. While his scandal did embarrass his party, Vitter was able to ride it out. McAllister, meanwhile, is simply a generic Republican from a safe district who owes his recent election as much to knowing reality television stars as to his political abilities.

There are long books and ongoing debates about whether the personal lives of adulterous politicians should be held against them. But it is clear that if politicians in Louisiana want to fool around, they need to have protection, both prophylactic and political.