Question: Who worked for Scarface and is a suspect in the St. Valentine's Day Massacre? 
Sentence (from "Gus Winkler"): Gus Winkler (March 28, 1901 – October 9, 1933) was an American gangster who headed a Prohibition-era criminal gang specializing in armed robbery and murder for hire with Fred "Killer" Burke.
Relevant evidence: Yes