The chances of Mike Cronin becoming a Chicago cop, let alone a legendary one, were slim.
A landmine left him temporarily blinded and blew off his left foot and part of his leg in 1968, when he was a Marine fighting in Vietnam.
After returning to Chicago, Mr. Cronin got a job as a mechanic servicing CTA trains. He was eager to join the Chicago Police Department and tried but couldn’t get in because of his injury.
Then, in 1971, a close friend who was a cop assigned to Mayor Richard J. Daley’s security detail told Daley about Mr. Cronin. The next thing he knew, Mr. Cronin was called downtown and invited to apply again and was hired.
A product of a North Side Irish Catholic working-class neighborhood, he asked to be assigned to the busiest part of the city — the West Side. He became a tactical officer in a gang unit.
Mr. Cronin, who used a prosthetic to walk, didn’t just do his job and go home. He came to know more about particular gangs than many the gang’s members and leaders. He wrote his observations in notepads that fit in his breast pocket, filling hundreds of them.
“Mike Cronin was probably the best street cop I’ve ever met,” said former police Supt. Phil Cline.
As a cop, he learned nicknames and gang lingo, monitored gang activities and drug sales, helped put Chicago gang leaders behind bars and built a reputation for fairness and fearlessness.
“He was a hero over in Vietnam, and he was a hero here in Chicago for all the cases that he made and the information he had, and nobody was better at developing informants,” said Cline, noting that Mr. Cronin also became proficient at securing and running wiretaps.
Mr. Cronin died Nov. 9 from natural causes, according to his family. He was 81.
As technology became a key part of fighting crime, he remained convinced that the best information still came from just talking with people. People who knew. him said he treated everyone with respect, including gang members.
“But, when they cross the line, he knows how to be the police,” former Deputy Supt. John Risley said in an interview for a Chicago Sun-Times story in 2006 marking Mr. Cronin’s mandatory retirement at 63.
Gang members knew him as “Cronie.”
“He wasn’t a hardass, he was someone people could talk to, and his forte was creating an intelligence network of people who would tell him things,” said his brother Jim Cronin. “It was an all-consuming job for him. He was a bulldog. He never married, didn’t have children, and he put hours and hours in.”
Mr. Cronin was deputy chief of the department’s Narcotics and Gang Investigation Section when he retired.
“He was, all-around, the best policeman we have had in Chicago in the past 50 years,” former Cook County State’s Attorney Richard Devine told the Sun-Times for the 2006 story upon Mr. Cronin’s retirement.
After his retirement, Mayor Richard M. Daley — whose father went to bat for Mr. Cronin decades prior — brought Mr. Cronin back as a civilian consultant to the police department, a role he held for two years, his brother said.
Mr. Cronin was born Dec. 11, 1943, to Michael and Mary Cronin, Irish immigrants. His father operated a CTA L train and later worked for a union that represented CTA workers. His mother worked as a bookkeeper for a credit union.
He grew up in Edgewater and was a member of St. Gertrude Catholic Church. He attended the parish elementary school and DePaul Academy.
His career was the subject of the self-published book “On the Street Doing Life: The West Side of Chicago Through the Eyes of a Cop Called Cronie” by former Chicago Tribune reporter Anne Keegan, a good friend.
Stories of working with Mr. Cronin were exchanged at his funeral, which drew a slew of Chicago cops, including two former police superintendents, and a number of former Cook County judges and prosecutors, Mr. Cronin’s brother said.
In recent years, Mr. Cronin split his time among the Chicago area, Florida and northern Wisconsin, where he enjoyed biking and playing pickleball and bocce ball.