Today marks the 40th anniversary of the incident at Chappaquiddick, the 1969 joyride that ended in the drowning of Mary Jo Kopechne, and left a permanent mark on the legacy and conscience of Sen. Ted Kennedy.

To mark the anniversary, we thought it would be fun to make a list of lessons learned from political scandals. In doing so, we discovered that the lesson of Chappaquiddick is, "It's not funny if people died." (Notwithstanding this satirical Volkswagen ad from National Lampoon.)

After the jump, we sift through the non-lethal sex scandals to glean important lessons about how to succeed in infidelity.

John Ensign and Mark Sanford

Within two weeks of each other, Nevada Senator John Ensign and South Carolina Governor Mark Sanford each held a press conference to announce they'd had an affair. (No, not with each other, although that would have been an awesome story.) Usually, the press conference comes after you get caught.

Lesson Learned:

Don't tell anyone you're cheating. You may think you're earning Brownie points by coming clean when you don't have to, but telling on yourself doesn't lessen the impact of an affair. No matter how guilty you feel, keep your dirty secret until the media breaks it.

Mark Foley

Ex-Florida Congressman Foley was forced to resign when news broke that he was IM-ing underage male congressional pages. Several of them went on to allege post-18th-birthday affairs with Foley.

Lesson Learned:

Check ID. After years of "Dateline:NBC"'s Chris Hansen asking mustachioed pervs if they know who he is, you should already know this.

David Vitter

The Louisiana Senator was implicated in the DC Madam scandal when his phone number showed up in her records. Vitter admitted his sin, but let everyone know that God had forgiven him. Now, he's set for a long, hard campaign against porn-star-turned-Senate-candidate Stormy Daniels.

Lesson Learned:

Call on the big guy if you have to. When Vitter got a pass from God, everybody else gave him one, too. He's still in the Senate and faced no censure of any kind.
Bill Clinton

If you're too young to remember the Lewinsky affair, you probably shouldn't be reading this article. The former President, and converter of the Oval Office into the Oral Office, was impeached after his taste for interns became public knowledge.

Lesson Learned:

Don't leave physical evidence. The destruction of Bubba's plausible deniability at the hands of that little blue dress make clear that aim is key. Just as damaging but more insidious than DNA: earrings, that perfume aroma, stray panties, etc.
Gary Hart

The former Colorado Senator was within a hair of the presidency when news of his affair with model Donna Rice broke. The iconic evidence is a photo of Hart, Rice in his lap, wearing a T-shirt emblazoned with the name of their love boat: "Monkey Business."

Lesson Learned:

Do not give fate the finger.
If you mess around, and you choose to flaunt your infidelity on a boat named "Monkey Business," you deserve to get caught.
Eliot Spitzer

The then-New York Governor was outed as a client of the Emperor's Club, which has nothing to do with penguins. As part of a criminal investigation of the high-priced prostitution ring, it was revealed that Spitzer had paid runaway-turned-prostitute Ashley Dupre $4500 a night for sex.

Lesson Learned:

Watch how much you spend on your philandering
. Wifey's bound to notice if too much money starts to disappear from the old joint account (or if she starts to notice transactions from say, Tiffany's or Frederick's of Hollywood). Oh yeah, and always use cash.