First suspected: First suggested in Bob Hinton's From Hell, later in Stephen Wright's Jack the Ripper: An American View.
Reasons for suspicion: George Hutchinson's description of the man he saw outside of Kelly's room on the night of her murder was exceptionally detailed - too detailed, some believe. Also, the fact that he withheld his evidence until after Kelly's inquest was completed seems suspicious.
Problems with candidacy: Police at the time interviewed him but did not seem to consider him a suspect.
How popular is this suspect?