Parker recalls facing racial discrimination in her childhood, and she was encouraged by her parents to improve the conditions of Black people.

[14] In 2013, Parker won a record $15 million judgment against an immigration consulting business that preyed on and defrauded immigrant families seeking legal residency in the U.S.[15] In September 2017, Parker and San Francisco City Attorney Dennis Herrera filed lawsuits against the top five largest investor-owned oil and gas companies.

But in 2022, a federal judge rejected this bid, allowing Oakland and San Francisco to continue prosecution of their climate justice and public nuisance lawsuits in California courts.

[16] In 2015, Parker sued the giant chemical company Monsanto to hold it accountable for "vast contamination" of Oakland's storm water system and the San Francisco Bay.

[17] Parker's office also filed a federal lawsuit against Wells Fargo to recover damages caused by predatory and discriminatory mortgage lending practices by the bank against African American and Latino borrowers.

[19] Parker co-authored a comprehensive ethics reform act adopted by the City Council in 2015,[20] and her office has required landlords in Oakland to fix substandard living conditions.

The law makes it a crime to leave firearms, magazines or ammunition unsecured in unattended vehicles on city streets and in other public places.

[23] Parker's office spearheaded a campaign to crack down on illegal dumping in Oakland using videos and other evidence submitted by the public.

[25] In January 2018, the Alameda County Bar Association recognized Parker's Office with the Distinguished Service Award (Law Firm of the Year).