Writing by the Seat of Your Pants: At the time the first installment was released to the public, King hadn't even figured out the ending yet... but still a set release scheduled for it. The return of Mr. Jingles at the end only came about because his wife literally asked him What Happened to the Mouse?, after King had completely forgotten about him.
Scully Box: To make 6'5'' Michael Clarke Duncantaller. Specifically, to tower over David Morse (Brutal, 6'4'') and James Cromwell (Warden Moores); at 6'7'', Cromwell is one of the tallest actors in Hollywood, but you wouldn't know it from this movie. John Coffey is only 6'8" in the book, but in the movie, he appears to be close to eight feet tall.
Throw It In!: As Del is getting ready to be electrocuted, he recites to himself the Hail Mary prayer in Cajun French; Michael Jeter ad-libbed this.note Though in the book, he did recite the Lord's Prayer in Cajun French with the reverend that administered his last rites.
Originally, Tom Hanks was going to play the older Paul Edgecomb, but the makeup tests did not make him look credible enough to be an elderly man. Dabbs Greer was cast instead as the older Paul Edgecomb.