WASHINGTON Sen. Kamala Harris (D-Calif.) on Monday addressed questions about her long history as a California prosecutor shortly after announcing her campaign for president in an appearance on ABCs Good Morning America.

In recent weeks, Harris has faced criticism from some on the left about her record as a district attorney in San Francisco and later as Californias attorney general. In a widely shared New York Times op-ed , law professor Lara Bazelon called Harris a regressive prosecutor who was often on the wrong side of history on the matter of criminal justice reform, as well as someone who fought tooth and nail to uphold wrongful convictions in California.

Prominent Bay Area activist Blake Simons also accused the senator on Twitter of terrorizing Black communities by working to strengthen the states prison system.

In her first press conference as a presidential candidate on Monday, Harris said she took responsibility for decisions she made a prosecutor and expressed regret for not being able to do more in certain cases she was involved in.

I can tell you of the cases where I really regret that we were not able to charge somebody that molested a child but the evidence wasnt there. There are cases ... where there were folks who made a decision in my office who did not consult with me and I wish they had. But again, I take full responsibility for those decisions, Harris said at Howard University, her alma mater.

But Harris made no apologies about her career, stating that there is a lot about what I did as a prosecutor that Im proud of, including starting a first-in-the-nation program that offered first-time nonviolent offenders a chance to have their charges dismissed if they completed vocational training.

There are fundamental flaws in the criminal justice system and ... this criminal justice system needs to be reformed, she said.

Harris campaign slogan, For the people, is more evidence she is embracing her background as a prosecutor despite the criticism from some progressives. According to The San Francisco Chronicle , the line is a reference to how she began her introduction to the court as a prosecutor: Kamala Harris , for the people.

On Monday she also responded to questions about her decision to defend Californias choice to deny sexual reassignment surgery to a trans inmate . She said she was obligated to defend the states positions as attorney general and that unfortunately she was sometimes forced to take stances contrary to my beliefs.

But the bottom line is the buck stops with me, and I take full responsibility for what my office did, Harris said.

Harris is the latest high-profile Democrat to declare her intention to run against President Donald Trump in 2020. Sens. Elizabeth Warren (Mass.) and Kirsten Gillibrand (N.Y.), along with former Obama Cabinet member Julin Castro , Former Rep. John Delaney (Md.) and Rep. Tulsi Gabbard (Hawaii), are running as well.

CORRECTION: A previous version of this story indicated Delaney is a current representative. In fact, his term ended in January.