Question: How many homicides did a serial killer confess to before his execution and were investigated by Robert D. Keppel?
Sentence (from "Ted Bundy"): Theodore Robert Bundy (born Theodore Robert Cowell; November 24, 1946 – January 24, 1989) was an American serial killer, kidnapper, rapist, burglar and necrophile who assaulted and murdered numerous young women and girls during the 1970s, and possibly earlier.
Relevant evidence: Yes