Estes also told liveabout.com that his prior experience playing a Marine prepared him for portraying a cop on Blue Bloods. "That action kind of transfers over," he said. Before Blue Bloods, Estes' most prominent role was on the ABC drama American Dreams as JJ Pryor, a Marine who fought in Vietnam.
"I know the police force likes the Marines," he added. "You have to have 60 college credits in order to join the New York police force or have been in the military." Estes is correct in this assertion, according to nyc.gov. Qualifying military service is one of the main reasons why so many police officers are also veterans.
Estes told liveabout.com that he hoped to do a ride-along and hang out at a precinct house to get to know some real cops. We can't confirm if he ever did a ride-along, but Vanessa Ray, who plays Jamie's NYPD partner-turned-wife Eddie Janko-Reagan, told Niagara Frontier Publications in 2014 that she and Marisa Ramirez, who plays Detective Maria Baez, did a ride-along, so maybe Estes did a tag-along.
Blue Bloods is currently in its 11th season on CBS, and airs Friday nights at 10/9c. Prior seasons are available to stream on Hulu and CBS All Access.