As far as Los Angeles County is concerned:
- The first turning point was in the early 1980's, when someone in the US government decided to direct the operation of CIA drug trafficking to Los Angeles County, California (part of the Iran-Contra Scandal). Effectively, it rendered the county an extra-constitutional zone. It also required collusion by all state and US justice agencies in undermining the law.
- The second turning point was the Rampart scandal (1998-2000), when it turned out that LAPD followed suit, and was by then in fact the drug purveyor to the county. The scandal also showed that the courts were directly involved in the illicit drug marketing, through the large-scale false imprisonment of innocent people as the drug dealers. By that time, the federal agencies could not say a word, and only colluded in the cover up.
- The third turning point started in the early 2000's, when the courts shifted their primary racketeering efforts to mortgage and real estate fraud in collusion with Countrywide, which was based in LA County. It was at least in part the outcome of banking deregulation by the US government. By the early 2000's LA County was already recognized by FBI as "Fraud Capital, USA" and in official reports as "the epicenter of the epidemic of real estate and mortgage fraud".
- The fourth turning point started 2008, with the collapse of Countrywide, and the initiation of fraudulent foreclosures in the courts.
Such detailed information is not available for the rest of the US, perhaps New York and Chicago (Cook County) may have comparable data. However, the big picture trend is similar across the United States.