WASHINGTON (Reuters) - U.S. Senator Kamala Harris launched her 2020 White House campaign on Sunday with attacks on President Donald Trump’s policies at a rally in her hometown of Oakland, California, less than a mile from the courthouse where the Democrat began her career as a prosecutor.

The event’s location was the latest sign she plans to emphasize her track record as San Francisco’s district attorney and California’s attorney general. Her 2020 slogan, “Kamala Harris, for the people,” nods at the introduction she used in court and is a phrase she calls her “compass.”

“My whole life, I’ve had only one client: The People,” Harris said at the rally, mentioning fighting for sexual assault survivors and prison diversion programs she created as a prosecutor.

The only former top city and state prosecutor in the race so far, the first-term California senator’s roots will differentiate her in a crowded field of Democrats seeking to run against President Donald Trump, the likely Republican nominee. Senators Elizabeth Warren and Kirsten Gillibrand are in the race, and more U.S. senators are weighing bids.

Harris blasted Trump’s push for a wall on the border with Mexico, saying it would not halt gangs trafficking in drugs, guns and human beings.

“On the subject of transnational gangs, let’s be perfectly clear. The president’s medieval vanity project is not going to stop them,” Harris said.

She also attacked the Trump administration’s separation of thousands of immigrant children from their parents at the southern border last year.

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“When we have children in cages crying for their mothers and fathers, don’t you dare call that border security. That’s a human rights abuse! And that’s not our America!” she declared.

Harris’ sharp questioning of Trump administration appointees and officials during Senate hearings made her popular with liberal activists. But her law enforcement background also carries risk in a Democratic Party that has shifted in recent years on criminal justice issues, embracing the Black Lives Matter movement and calling for body cameras for police, the end of the death penalty and sentencing reform.

Her actions as attorney general from 2011 to 2017 on those issues angered some liberals, and critics revived the #KamalaisaCop hashtag on Twitter after she announced her campaign last week.

“Harris will have to figure out how she’ll convince the (progressive) movement that she’s their champion when many organizers and activists are on record criticizing her approach as attorney general on issues related to prison overcrowding, police shootings and marijuana legalization,” said Waleed Shahid, spokesman for Justice Democrats, a group supporting progressive candidates.

PROGRESSIVE PROSECUTOR?

Harris, 54, is the daughter of a black father from Jamaica and an Indian mother who met as activists during the U.S. civil rights movement in the 1960s.

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She touts her work as attorney general reaching a settlement with major banks involved in the foreclosure crisis, which hit minority homeowners particularly hard.

She also implemented an implicit bias training for law enforcement officers and declined to defend a state ballot proposition prohibiting same-sex marriage.

She refers to herself as a “progressive prosecutor.” But University of San Francisco law professor Lara Bazelon says Harris’ “record on wrongful convictions alone is disqualifying” for that title.

Civil rights activists have criticized Harris’ attorney general’s office for defending a “three strikes” law. As a district attorney, however, she only pursued 25-to-life sentences on a “third strike” that was a serious or violent felony.

At a press conference following her White House announcement, Harris said she took “full responsibility” for her offices’ work, adding as a government lawyer she did not always agree with her clients.

“This criminal justice system needs to be reformed,” Harris said. “The bottom line is the buck stops with me.”