How did Alcatraz inmate Alvin Karpis get the nickname "Creepy"?

Question

I was in Alcatraz two days ago and I heard of this interesting inmate named "Creepy" Karpis who taught Charles Manson how to play guitar...anybody know how he got the nickname "Creepy" when he was in Alcatraz?

Answer 1

Alvin Francis "Creepy Karpis" Karpowicz (August 10, 1907 – August 26, 1979), was NICKNAMED "CREEPY" because of his SINISTER SMILE.  Born in Montreal, Quebec and raised in Topeka, Kansas, he was known for his alliance with the Barker gang in the 1930s.  He was the last "public enemy" to be taken, a capture which elevated J. Edgar Hoover and the Federal Bureau of Investigation (FBI) to national prominence.

Even after the Barkers were apprehended in 1935, Karpis eluded capture for another 15 months, eventually taken into custody in New Orleans in May 1936. He was 28 years old. Three months later (in August 1936), Karpis found himself the newest resident of Alcatraz island. He arrived just after the prison opened and left just before it closed in 1962.

Answer 2

The official explanation says his cold stare gave everyone the creeps.  The unofficial explanation says it's because he was g*y(those were much less enlightened and politically correct times).