LORELAI: So if Rachel turns out to be an evil fembot and murders Luke in his sleep, I’m not responsible am I?
RORY: Only in an intergalactic court.
Lorelai is probably referring to the 1997 comedy film Austin Powers: International Man of Mystery, directed by Jay Roach and starring Mike Myers in the title role. In the film, a parody of spy movies, a mad scientist named Dr. Evil has a gang of sexy female robots (fembots) who wear silver outfits and have weapons in their breasts that can kill: they are just one of the many traps that Austin Powers and his assistant must get through.
The fembots are taken directly from the 1965 comedy film Dr. Goldfoot and the Bikini Machine, directed by Norman Taurog and starring Vincent Price in the title role. However, in this case the female robots are programmed to seduce and rob wealthy men, rather than murder anyone. In the 1966 sequel Dr. Goldfoot and the Girl Bombs, they are rather more explosive.
Austin Powers: International Man of Mystery was a commercial success and received good reviews. Susanna Hoffs from The Bangles (married to the director) performed on two songs from the film’s soundtrack, which seems like one reason why Lorelai would have wanted to see the film.
Galactic (and intergalactic) law courts are a common trope in science fiction film and television. Some of the earliest examples can be found in the original series of Star Trek, previously and freqently mentioned.
Lorelai and Rory’s exchange seems inspired by the sci-fi film they are watching.