Gumshoe is something often seen demanded of Justin Robert Young by the chat room. This is a request for Justin to impersonate the voice of Lynne Thigpen as "The Chief" from the 1991-1995 game show, "Where in the World is Carmen Sandiego?" In the game show, The Chief would give instructions to contestants by referring to them as "gumshoes". Justin's impersonation is now known as the "gumshoe voice".
Where in the World is Carmen Sandiego clip
From the episode "Shoo Trees":