Marvin Margolis (also known as Marvin Merrill) was named by investigative consultant Alex Baber as a suspect in both the Zodiac killings and the 1947 “Black Dahlia” murder of Elizabeth Short. According to Baber, Margolis was a former U.S. Navy corpsman with medical training who had a documented relationship with Short and appeared among suspects in the Los Angeles County grand jury investigation into her death. Baber claimed to have decrypted the Z13 cryptogram to reveal the name “Marvin Merrill,” and pointed to alleged access to a military bayonet resembling the Lake Berryessa attack weapon, handwriting similarities, and geographic proximity to crime scenes.
Baber’s findings were reported in the Los Angeles Times in 2025 and presented to multiple agencies, none of which publicly confirmed his conclusions; Margolis was never officially named by law enforcement. In May and June 2026, Dave Oranchak — credited as one of the three people who solved the Z340 cryptogram — published a three-part YouTube series characterizing Baber’s investigation and accusations as a complete hoax and fraud.
Conflicting accounts
Baber asserted Margolis’s guilt in both cases; Oranchak’s series concluded the theory was fraudulent, and no agency confirmed it.