More than a year ago, a source in the San Francisco District Attorney's office told me the city's new DA, Terence Hallinan, was plea-bargaining criminal cases at a disturbing pace, and many serious criminal charges were being dismissed in the process.
The tip was intriguing, but I needed to find some way of checking it out short of simply examining every case Hallinan's office had handled – a daunting task given the thousands of cases filed annually.
Late last year, I discovered a type of data called Offender Based Transaction Statistics (OBTS) that was used by the California Attorney General's office to generate a section of the state's annual report, "Crime and Delinquency in California." The information is known as "Adult Felony Arrest Dispositions," available from the Criminal Justice Statistics Center of the state Department of Justice.