In the film, the Toon Patrol are the law enforcers of Toontown, although they behave less like law enforcers and more like gangsters and crooks due to their behaviors. Judge Doom has hired them to arrest Roger Rabbit for the murder of Marvin Acme. Their vehicle is a real-life black 1937 Dodge Humpback panel truck which serves as a paddy wagon. The vehicle is fitted with official City of Los Angeles "Toon Patrol" decals on the front doors.
Like all the other Toons in the movie, the Toon Patrol are invincible to physical body harm except the chemical blend called "The Dip".
In the case of the weasels, it is shown that prolonged laughter is also lethal to them; while Eddie Valiant jokes around in front of them during the climax of the film, all except their leader Smarty die from laughing at him; Smarty meets his demise after Valiant crotch-kicks him into a vat of The Dip. Whether or not the weasels knew that Doom was a Toon himself is never confirmed, but their relationship with him may hint that they had no knowledge of such.
Eddie with a switchblade. He is the smartest, cleverest, and wittiest of the weasels. He is also arrogant, bossy, and a bit fussy. Although very sarcastic, he is the straight-man of the group, possessing the most self-control and least "toony" attitude. While he is very antagonistic in the film, he seems to care about the other members of the Toon Patrol, always being the one to warn them about what might happen to them if they can't control their laughter. However, like them, he still enjoys a good laugh, himself. He commits a malapropism almost every time he speaks, such as when he says that a tip on Roger's whereabouts has been "corrugated" ("corroborated") by several sources. He is the third weasel to die at the end of the film, although not by losing control of his laughter. Upon disagreeing with a lyric in the song Eddie "entertains" the weasels with, Eddie kicks him in the crotch, sending him flying into the mixer on the Dip Machine, where he dissolves and dies. Unlike the other weasels, his ghost doesn't appear; this is because the Dip is meant to completely destroy a toon so there would be no toon ghost.
1940s. Like his compatriot Stupid, Greasy is overweight, although this does not appear to have affected his self-esteem. Of all the weasels in the film, Greasy is most eager to fight, and yields a switchblade as his weapon of choice, though he is also seen carrying a semi-automatic pistol while investigating Eddie's office. Greasy is mostly shown speaking English with a strong Puerto Rican accent, but he curses in Spanish when a bear trap hidden in Jessica's cleavage clamps down on his hand as he frisks in between her breasts, and when Roger shoots into the Acme Factory via a storm drain, carrying Greasy (who was standing on top of it) with him towards the ceiling. He appears perverted, as he quickly takes Judge Doom's orders to search Jessica for Marvin Acme's will as an opportunity to feel her and immediately goes for her cleavage. Greasy is the fourth weasel to die after losing control of his laughter and drops dead out of the cab of the Dip machine. He also made the Dip machine move because his foot came off the brake when he fell out of the driver's seat as he died from laughter.
Roger and Jessica, when he says, "Time to kill the rabbit! Hee-hee-hee-hee-hee!", and when he says, "Bye-bye!" after he dies. He gets excited by the concept of killing, as he is heard gleefully laughing when Judge Doom kills the Toon Shoe in the bucket of Dip. He is nearly drooling in anticipation as Smarty attempts to drive into Benny the Cab, and he takes it upon himself to shoot the Dip at Roger and Jessica. On a few occasions, it is implied that he enjoys pretending his straitjacket is buckled by hugging himself tightly, namely when he exits the Toon Patrol's car in his first appearance, and while laughing after Eddie stuffs a bar of soap into Smarty's mouth, though this might also imply that he is not entirely used to having his straitjacket unbuckled. He remains a threat after his death; he loses control of his laughter and hits the switch that turns on the Dip nozzle before he loses his balance and falls off the platform. In an attempt to save himself, he hangs on to the yellow handle, pulling it down and making the nozzle turn left, but he still slips off into the giant spinning brush below. His soul rises up like the others, but instead of just doing nothing, he turns the pressurized Dip spray back at Roger and Jessica. He is the last weasel to die not only by losing control of his laughter, since his soul appeared, but also by losing his footing and falling onto the giant rotating brush of the Dip Machine, where he likely got flattened to death and later dissolved in Dip.
During production, there were going to be seven weasels rather than five, much like the Seven Dwarves. The other two were named "Slimy" and "Flasher." Other names considered were Crazy, Sleazy, Scummy, Itchy, and Twitchy. However, only Slimy and Flasher made it to the sketch stage and no voice work for them was ever completed. Slimy was a black weasel with 1950s greaser attire who puked slime (and, just by looking at his concept art, could also be playing in it) and carried a blackjack as a weapon. Flasher, as his name implies, wore a trenchcoat, but did not carry a visual weapon. The conceptual art of these characters is included in the 15th anniversary DVD edition of Who Framed Roger Rabbit?.
Also, there is an unnamed weasel in Roger Rabbit's Car Toon Spin. He is a dark brown weasel who wears a gray baggy hat, a white button-up shirt, and dark cadet-blue baggy suspenders. He was voiced by Will Ryan. His origins are unknown, though some names have been suggested by fans, notably "Sleazy."