Well, they were just left laying around ... underground.
Apparently, mac 'n alcohol may have been the issue here.
Source: Associated Press
The movie was a comedy; Archer-Gilligan's multiple murders, not so much.
[September 15, 2015] The Connecticut Supreme Court voted to keep sealed the medical and psychiatric records of Windsor serial killer Amy Archer-Gilligan, the inspiration behind "Arsenic and Old Lace" ...