The film is based on an actual case known as the "Career Girl" murders that happened on 28 August 1963. It was the date on which Martin Luther King delivered his "I Have A Dream" speech, as mentioned in the film.
After Telly Savalas died, the movie was shown again for the first time in nearly 20 years, this time with a short clip of Telly and the words "Dedicated to the memory of Aristotle 'Telly' Savalas 1920 - 1994" at the end of the show.
After the great success of this TV movie and the subsequent Kojak (1973) series, the author of the original book, Selwyn Raab, pointed out with some acerbity that, in real life, the uncovering of a gross injustice had been the work of crusading journalists, not police officers, adding that he had never met a real-life cop like Theo Kojak.
Telly Savalas' real-life brother George Savalas appears in this film, but playing a different character to the Det. Stavros character he would play throughout the later Kojak (1973) TV series.
"The Marcus-Nelson Murders" was originally written as and intended to be a feature film but no studio wanted to produce it due to its negative portrayal of the police force.