Pete Buttigieg has so far enjoyed a relatively easy ride in the Democratic primary. The 37-year-old entered the race as something of a novelty act—the baby-faced mayor of a small midwestern city—but quickly rose toward the top of the crowded field on the strength of his personal charisma and his message of generational change. But now, a racially-charged tragedy in Buttigieg’s home city has underscored one of the mayor’s biggest political vulnerabilities—and raised questions about his sensitivity to issues facing communities of color.

Buttigieg faced intense scrutiny Sunday from South Bend residents as he fielded questions about the shooting of a black man by a white police officer last weekend. “We don’t trust you!” a woman in the audience shouted at the Democratic hopeful at one point. Buttigieg briefly left the campaign trail last week after South Bend Sgt. Ryan O’Neill shot and killed 53-year-old Eric Jack Logan while investigating a report of car burglaries. O’Neill claimed that Logan was brandishing a knife, but activists in the city have raised questions about the incident, especially considering O’Neill did not have his dash or body camera on at the time. Buttigieg attempted to address the issue Sunday, responding to residents’ questions about both the shooting and racial issues within the city as a whole under his leadership.

The crowd, however, appeared unconvinced. “You might as well just withdraw your name from the presidential race,” said one audience member, per the Chicago Tribune. “His presidential campaign is over. I believe that today ended his campaign.”

Buttigieg acknowledged his shortcomings on issues of race; South Bend in general has been plagued by racial tensions, and he personally came under fire in 2012 shortly after taking office for firing Darryl Boykins, South Bend’s first black police chief, for allegedly attempting to blackmail officers who were apparently taped using racist language about him. (Boykins sued the city for racial discrimination over his firing and won $50,000 in 2013.) “At the end of the day, I’m responsible,” Buttigieg told residents Sunday as he responded to questions about issues ranging from the failure of body cameras to a lack of diversity on the police force, which has worsened under his watch. “The effort to recruit more minority officers to the department and the effort to introduce body cameras have not succeeded and I accept responsibility for that,” he went on. “We have tried but not succeeded to increase diversity in the police department and we need help.” He called on the Justice department’s civil rights division to investigate the case, and said he’s open to meeting with African-American leaders, even as he suggested that activists “decided not to join” discussions with his office. “I am always trying to get more voices heard,” Buttigieg said. “I don’t want to sound defensive, but we have taken a lot of steps. They clearly have not been enough, but I cannot accept the suggestion we have done nothing.”

The contentious meeting highlighted, and could very well exacerbate, Buttigieg’s struggle to connect with black voters. Though he’s polled well overall, surveys at the beginning of May showed him at just 2 percent among African-Americans. Pollster Ron Lester suggested to the Tribune that the lag might be due to a lack of familiarity: “Black voters have more of a wait-and-see attitude than a lot of other Democratic voters when it comes to evaluating white candidates,” he noted. And yet, the heated meeting Sunday suggested that the low numbers may stem directly from Buttigieg’s actions. His constituents also appear to be frustrated with their mayor’s campaigning—“You gotta get back to South Carolina like you was yesterday?” one remarked. It’s a familiar problem for any mayoral or gubernatorial candidate, but in Buttigieg’s case, his perceived absence could inflame the situation in South Bend.

In his unlikely rise to the top tier of Democratic candidates, Buttigieg received relatively less scrutiny than his better-known counterparts. With his hometown scandal, Buttigieg is now facing what could be the biggest test of his candidacy. How he handles it could make or break him, both at home and in the Democratic primary. “This was a trail of gasoline that was waiting to be ignited,” South Bend pastor Mario Sims told the Tribune. “Last week, it ignited.”

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