What is the name of the informant that Terry Malloy helps to lure the rooftop to be killed at the beginning of the film, On the Waterfront?

On the Waterfront (1954) was a leading movie which give the American public a picture about bad cops and union violence and corruption among longshoremen in the U.S.

In this 1954 movie, Joey Doyle is the character played by Elia Kazan. He is a young longshoreman who is murdered in the film for his testimony to the Waterfront Crime Commission. His (Joey’s) shadowed head from his apartment window is seen only in a long shot, then his body falls from the roof to the ground. Joey's death becomes the ghostly presence that overrides this film, as well as the spark that kick starts all subsequent events on and off the docks.

Other key characters in On the Waterfront are Kayo Dugan, Charley Malloy, and Johnny Friendly. They are respectively (1) a short, strong longshoreman who testifies to the Waterfront Crime Commission and is murdered on the job for it.; (2) Terry Malloy's brother and Johnny Friendly’s educated right-hand man, and (3) the vocal and corrupt leader of the Longshoreman’s Union who is a tough criminal that had to claw his way to the top.