Douglas Herlihy admitted to killing his father in a New Hampshire home in 2003. A closet door message and a 2020 boast to police helped crack the case.
https://www.foxnews.com/us/man-admits-beating-dad-death-picturesque-town-decades-ago-bragging-cops-first-body
https://www.foxnews.com/us/man-admits-beating-dad-death-picturesque-town-decades-ago-bragging-cops-first-body