The retired Phoenix-area law enforcement officials said they joined the Respect Arizona recall campaign after Arpaio apparently sent a letter to supporters filled with what they described as scare tactics.
The letter warned that crime would spiral out of control if Arpaio was forced out of his long-time post as sheriff of Maricopa County, The Arizona Republic said Thursday.
Former high-ranking officials of the Phoenix police force and federal and state prosecutors took umbrage at the idea Arpaio was holding himself out as the only person standing up to crime in the area.
"Arizona law enforcement will continue to fight crime and ensure public safety long after Mr. Arpaio leaves office," former Phoenix police chief Jack Harris said in a written statement.
Arpaio's camp said in response that the sheriff's long-running hard line against illegal immigrants had indeed helped keep a lid on crime.
"If it doesn't matter who the elected official is, then why do they want to remove Arpaio from office? They want him out of office precisely because of the way he runs his office, specifically as it relates to enforcing illegal immigration laws," campaign manager Chad Willems said in an e-mail to the newspaper.