In 1980, 18 year old Marilyn McIntyre was brutally murdered in her own home. Her murder went unsolved for 30 years, until police were finally able to arrest a suspect that they had been suspicious of all along.
Sources:
48 Hours – The Last Chance for Justice
Exhumed Season 1 Episode 2 – Cold Case, Unearthed
https://www.nena.org/page/911overviewfacts
https://www.cbsnews.com/news/48-hours-last-chance-for-justice/
https://www.sandiegouniontribune.com/sdut-exhumed-victim-arrest-032709-2009mar27-story.html
https://casetext.com/case/state-v-forbes-53/
https://www.newspapers.com/image/407372186/