Wikisimpsons - The Simpsons Wiki
SpringShield was Homer's security agency. Though Homer, Lenny, and Carl were the only employees, they were much more efficient at fighting crime than the Springfield Police Department. Because of this, Mayor Quimby fired Chief Wiggum, and instated SpringShield as Springfield's police force.
SpringShield got out of control with all their laws. Homer eventually said that he would hand over chief of police to the next person he sees, who is Wiggum.