The animated Fox show "Family Guy" is known for pushing the political envelope, but what was up with last night’s catch phrase, "Laura Bush killed a guy"?

Loyal fans love the show for its politically incorrect humor –  it thrives on the "They did NOT just say that" variety of comedy.

But Sunday night’s episode left some viewers scratching their heads.

Lead cartoon characters Peter and Lois Griffin repeated the phrase "Laura Bush killed a guy" several times throughout the show with Peter was dressed as Mrs. Bush and Lois as a bleeding man crisscrossed with tire tracks for a costume party.

So where did they come up with that one?

Well, according to public police records, First Lady Laura Bush – then Laura Welch – was involved in a fatal car crash in Texas in 1963.

The report says 17-year-old Laura Welch ran a stop sign and was involved in a crash that killed a friend of hers in another car, the Associated Press reported.

"It was a very tragic accident that deeply affected the families and was very painful for all involved, including the community at large," said Mrs. Bush's spokesman, Andrew Malcolm told the Associated Press in 2000.

''To this day, Mrs. Bush remains unable to talk about it,'' he said.

The crash was reported on during President George W. Bush’s first run for the White House in 2000. According to the report, Mrs. Bush struck a sedan driven by 17-year-old Michael Douglas.

Rumors have swirled since the crash was first reported that Mrs. Bush may have been criminally negligent (i.e. that she may have been drinking) at the time of the crash, but no chargers were filed and no evidence of wrong-doing was recorded.

"Family Guy," created by Seth McFarlane, first went on the air in 1999. The show's leading dysfunctional family - the Griffins - live in a small Rhode Island town and among the celebrity voices behind the animated faces are Seth Green ("Austin Powers") and Mila Kunis ("That '70s Show"). The show has won three Emmy awards.

Laura Bush is certainly not the first political figure to be skewered by the show – recent plots linked Sen. John McCain and Gov. Sarah Palin to Nazis. It has mocked slavery, the disabled, the women’s movement, obesity and pretty much any other sensitive or controversial issue you could possibly think of.

Will it show President-elect Barack Obama the same (dis)respect? We’ll see.