John Keenan, 'Son of Sam' detective, dies

John L. Keenan, the retired NYPD chief of detectives who took part in the investigation and arrest of "Son of Sam" serial killer David Berkowitz in 1977, died Thursday at the age of 99, his family said.

Keenan, a resident of Rockville Centre, died peacefully in a hospital surrounded by Sara, his wife of 73 years, and others, his grandson Kevin Brennan said Friday.

 A veteran of World War II who took part in the D-Day invasion and the Battle of the Bulge, Keenan joined the NYPD in 1941 and then enlisted in the military, said an NYPD spokeswoman, adding that he retired in 1978.  Including his time on active military duty, Keenan served for 37 years with the police department, Brennan said.

Current NYPD Chief of Detectives Dermot Shea said in a statement Keenan lived "a life of epic heroism."

In a 2017 interview with Newsday, Keenan recalled the night Berkowitz was arrested in August 1977 and said the killer recognized the detective immediately.

 "I know who you are. You are Det. Keenan," said Berkowitz, according to Keenan.

 "Who are you?" Keenan asked Berkowitz.

 "I am the Son of Sam," Berkowitz replied, recalled Keenan.

Keenan, whose parents were Irish, was actually born in England in 1919, Brennan said. The English birth became something of a family joke.

“He would always joke that he could never be president because he was born in England,” Brennan said.

Keenan and his family settled in Manhattan shortly after he was born and then moved to Brooklyn.   After joining the NYPD, Keenan enlisted in the U.S. Army and served in the Counterintelligence Corps. During the early part of his military career, Keenan was stationed on Governors Island where he met his wife, who also happened to be working with that unit of the military, Brennan said. He was present for the liberation of Paris in August 1944,  his grandson said.

Returning to the NYPD after the war, Keenan rose steadily through the ranks, eventually becoming chief of detectives in 1977. Although he didn’t go to college immediately after high school, Keenan ultimately received a degree from the New York Institute of Technology.

Brennan said his grandfather was “an accomplished and brilliant man” who also was exceedingly humble. And he was a centerpiece of the family, his grandson said.

“He was the number one, the rock, central figure in our family and provided for us an example of how we should be the rest of our lives,” said Brennan, who like many in the family lives in Rockville Centre where Keenan and Sara moved in 1950.

 In addition to his wife, survivors include daughter Joan Brennan of Rockville Centre, son-in-law Kevin Brennan of Rockville Centre, five grandchildren and two great-grandchildren. Keenan’s other two daughters, Mary Ellen Keenan Carey and Sara Keenan, predeceased him.

Visitation is Sunday, 2-4 p.m. and 7-9 p.m., at Macken Mortuary, 52 Clinton Ave., Rockville Centre. Funeral Mass is Monday, 11 a.m., at St. Agnes Cathedral, Rockville Centre. Interment will be at Cemetery of the Holy Rood in Westbury.

By Anthony M. DeStefano

tony.destefano@newsday.comtonynewsday

Anthony M. DeStefano has been a reporter for Newsday since 1986 and covers law enforcement, criminal justice and legal affairs from its New York City offices.