SPRINGFIELD — A backlog of cases before the Illinois Office of the State Appellate Defender that the agency’s leader once described as a “crisis in the criminal justice system” has largely been resolved, State Appellate Defender James Chadd told a state Senate committee Tuesday.Chadd told a Senate judiciary appropriations subcommittee that the backlog of cases at one time exceeded 3,759 amid a two-year budget impasse and extensive periods of underfunding. There are now fewer than 500 cases with complete records before the …