The death of George Floyd in Minneapolis police custody this week has renewed concerns about Sen. Amy Klobuchar’s time as a Hennepin County prosecutor as she is being vetted as a potential running mate for Democratic presidential candidate Joe Biden.

The selection of Biden’s No. 2 is unfolding as many blacks — a key voting bloc for the party — are looking for Biden to show he is not taking black voters for granted and that his ticket can excite those who sat out the 2016 election.

Klobuchar’s presidential bid was marked by an inability to gain inroads with black primary voters while at the same time facing criticism from civil rights activists attacking her decisions not to prosecute any of the officers in a string of police-involved fatalities when she was Hennepin County attorney.

Klobuchar has condemned Floyd’s death and called for justice. But the incident, and the unrest seen nationwide, also has increased pressure on Biden to balance the Democratic ticket with a running mate closer to the activist base of the party.

“We need to close the enthusiasm gap that Biden currently faces. We need to have a VP pick that expands the capacity of the campaign to reach these key audiences. Black women are key. Brown women are key. And Klobuchar does not do that,” said Aimee Allison, president of political group She the People and organizer of the first presidential forum focused on women of color.

Even before the deadly police encounter in south Minneapolis, social media had burst with posts questioning Klobuchar’s ability to help Biden beat President Donald Trump in November. While Biden has vowed to choose a woman, some activists on the left and political scientists said her mainstream progressive politics add little to the ticket. Others have urged him to pick a woman of color.

Klobuchar has not commented publicly on her prospects as a vice presidential candidate. But complicating her appeal to the party’s left flank was the criticism she faced in the closing days of her presidential campaign from Black Lives Matter protesters and others angered by the disputed murder conviction of black teenager Myon Burrell during her days as a prosecutor.

An Associated Press investigation raised questions about the conviction of Burrell in the 2002 killing of an 11-year-old girl. The controversy sparked a protest that shut down the final Minnesota rally of her presidential campaign.

The Floyd case has put the national spotlight back on Klobuchar’s days as a prosecutor, particularly as it became clear Derek Chauvin, the officer involved in Floyd’s death, was involved in the death of another citizen while Klobuchar was prosecutor. Chauvin was one of six officers who fired on and killed Wayne Reyes in 2006 after Reyes reportedly aimed a shotgun at police after stabbing his friend and girlfriend. While the death happened during Klobuchar’s tenure at the helm of the Hennepin County Attorney’s Office, the case did not go to a grand jury until after she left the office and became a senator.

Klobuchar did not criminally charge other police involved in the more than two dozen officer-involved fatalities that occurred during her time as prosecutor. She left those decisions to a grand jury, a practice that was common at the time.

Klobuchar said in a CNN interview Tuesday that the evidence is “crying out for some kind of a charge” against the officers involved in Floyd’s death. Michael Minta, an associate professor at the University of Minnesota who studies political representation and race, said that is a departure from her more cautious responses to past cases.

“It’s that delicate balance” for both Klobuchar and Biden, Minta said. “Part of their appeal was being that moderate and not being perceived as being super far to the left on these issues. You can support good policing, but you can also go against bad policing.”

Klobuchar is not the only potential vice presidential pick whose law enforcement history has drawn criticism. Sen. Kamala Harris, as the former California attorney general, and Rep. Val Demings, who was an Orlando police chief, have contended with controversies that could mar their support.

Virgie Rollins, chair of the Democratic National Committee’s Black Caucus, said she feels Klobuchar’s history is being unfairly targeted now. She said people who are taking issue with her time as a prosecutor now should have raised their concerns earlier during the primary race. She said Klobuchar has worked hard to get where she is and ran a “brilliant” presidential campaign.

Minnesota Attorney General Keith Ellison, who was a lawyer and state legislator when Klobuchar held the prosecutor’s post, also defended Klobuchar’s record.

“The general and overall tone was that the office dealt fairly with criminal defendants within the law,” he said. “Now were there larger social movements that were of a concern? Yes. But they weren’t her fault.”

Klobuchar is “a door-open kind of person,” Ellison said, and if she were to become vice president, she would be accessible and ready to talk with people about their concerns.

But Klobuchar has struggled to make political inroads in diverse states, and exit polls from the South Carolina primary showed just 1% of black voters picked her. Some black nonprofit and political leaders and members of the media said she hasn’t sufficiently tried to connect with the community.

Rashad Robinson, president of the nonprofit Color of Change, said he tried to meet with Klobuchar two dozen times during her presidential campaign and never was able to do so. The podcast he hosted, “Voting While Black,” interviewed most of the other high-profile candidates, but she did not participate.

Biden would be making a safer bet by trying to energize voters who sat out the 2016 election or voted for a third-party candidate, rather than courting independents, said Adrianne Shropshire, executive director of BlackPAC.

“The question really is: What is the ticket that can bring those voters back into the fold?” Shropshire said. “Many of those voters happen to be young voters. They happened to be black men, and younger black men in particular. And those also happen to be the people we see out demonstrating in Minneapolis today.”