Many of the murder scenes were shot in the locations where the real-life murders took place.
To make sure Johnny Depp's performance was true to the real James "Whitey" Bulger, Scott Cooper hired some of Bulger's old associates as consultants to the film. Each of them praised Depp's performance, saying, "That's Whitey."
James 'Whitey' Bulger was killed October 30th, 2018, at United States Penitentiary Hazelton, near Bruceton, WV. Bulger was in a wheelchair, and had been there less than a day. He was beaten to death by multiple inmates armed with a sock-wrapped padlock and a shiv.
When Bulger was finally arrested, he was going under the name Charlie. That was also the code name for him as an informant.