Strange Bedfellows

It is said the cop killed was in 1978, so a life sentence without parole was not possible. The US Supreme Court had ruled the death penalty unconstitutional in 1972. Several NYPD officers were killed by gunfire in 1978.

The real-life basis here was a mix of a convicted cop killer from 1971 who was granted parole in 2018 and another from 1978 that was also granted parole in 2018. Similar to what was in the show, the first criminal ambushed not one but two police officers via a bogus 9-1-1 call and was originally sentenced to 25 years to life, as was the other criminal in 1980. The first criminal had also killed a police officer in California a few months after the NYPD killings, for which he received 5 years of probation due to California authorities mistakenly thinking he'd be in prison in NY for the rest of his life.

In 2008, the New York legislature changed the law and allowed parole even for criminals serving a life sentence. As was observed in the show, in recent years, the makeup of the parole board (under progressive governor Cuomo in real life) has resulted in numerous high-profile murderers receiving parole. One of the members of the board is married to a murderer she met while he was in prison, and she used her position to argue for his parole.

During the family dinner, Frank Reagan is buttering his roll. You can see his knife bend as it's really made of plastic. Real silverware and place settings made too much noise during filming and were replaced with fakes early on.