- This article is about the mafia member. For others name Louie, see Louie (disambiguation).
Louie is a member of the Springfield Mafia. He is most often seen accompanying his boss Fat Tony along with fellow 'muscles' Legs and occasionally Johnny Tightlips.
As seen in Springfield Up and The Blunder Years, he and Legs have been friends with Fat Tony since childhood, and they have been the playground bullies of their generation.
Louie has always been eager to please Fat Tony, doing whatever he's told and trying to make himself useful at all times, such as offering him a spare ketchup packet at a restaurant . He isn't afraid to kill or wound anyone who gets in his way. However, Louie has often shown fear of possibly angering his boss , or misunderstanding Fat Tony's words, even exclaiming at one point, "You know how it is with us! Everything means 'kill!'."  He has also confided in Legs that he doesn't know what Fat Tony exactly means when he gives an order to 'take care' of someone, and that he is afraid to ask for clarification because Louie himself might get 'taken care of' too. 
- He says that tear gas is "[his] one weakness," though this is likely an embellishment. 
- Along with Fat Tony and Legs, Louie has been seen attending the monthly pancake dinner at the Springfield Catholic Church. 
- He owns a 'Folk Diva Mix' CD that includes Janis Ian's "At Seventeen." 
- Louie confesses that he brings his own candy to movie theaters, much to Fat Tony's disappointment. 
||The contents of this article or section are considered to be non-canon and therefore may not have actually happened or existed.
The Simpsons: Hit and Run
Louie is a character you can talk to and have an optional street race for money.
Entry fee: 20 coins.
Payout: 80 coins.
When Apu asks him where the Buzz Cola trucks are coming from, Louie replies that they are related to the museum. He then threatens Apu not to tell anybody else about it, or else the mafia will come after his family.
The Simpsons Game
He is a character seen walking around Springfield, and can be recruited by Marge.
The Simpsons: Tapped Out
- This section is transcluded from The Simpsons: Tapped Out characters/Wise Guys. To edit it, please edit the transcluded page.
He appears in The Simpsons: Tapped Out on Level 28 along with Legs, with the Fat Tony's Compound Building.
Behind the Laughter
According to Dan Castellaneta, he modeled Louis' voice after the Italian American actor, Joe Pesci, who had a role in Goodfellas. A reference to him is also in Futurama as Clamps in the Robot Mafia.
On October 22, 2014, it was reported that Goodfellas actor Frank Sivero was suing Fox Television Studios and Matt Groening for $250 million, claiming 'misappropriation of likeness and ideas as well as unjust enrichment' over the show's use of Louie.  Sivero maintains that Louie's appearance and mannerisms are strongly evocative of his character Frankie Carbone in the movie, and he is claiming the money on the grounds that the Simpsons producers appropriated his “confidential idea” for the movie character, as well as for “loss of likeness”, resulting him to be subsequently typecast. 
||Wikisimpsons has a collection of images related to Louie.