Specifically, the case against defendant Angelo Buono was based largely on the testimony of co-defendant Kenneth Bianchi, who became uncooperative and unreliable, claiming to have multiple personalities and repeatedly changing his story.

Van de Kamp accepted their judgment and allowed the trial prosecutor, Roger Kelly, to move to dismiss all 10 murder charges against Buono and release him with an eye toward trying him for pandering.

The prosecutors from the Attorney General's office were able to overcome the problems with Bianchi's behavior, and went on to secure convictions on nine of the 10 counts and a life sentence against Buono.

In 1987, Van de Kamp unsuccessfully led the State's charge against pornography by defending the pandering conviction of adult filmmaker Harold Freeman.

Van de Kamp appealed to the United States Supreme Court, who declined to hear the case, thus effectively legalizing the production of adult films.

In February 1989, he brought an AK-47 assault rifle to a legislative hearing on gun control and told the lawmakers that he could kill them all in the time it took to utter a sentence.

Van de Kamp ran for the office in 1990, hoping to succeed Deukmejian a second time, but he lost the Democratic primary election to former San Francisco Mayor Dianne Feinstein.

After his loss to Feinstein, Van de Kamp retired from politics and with his wife returned to his hometown of Pasadena, California, where they lived until his death in March 2017.

[13] In 2016, along with Ron Briggs, Van de Kamp sued to overturn Proposition 66, a state constitutional amendment that sped up the death penalty process.