Tony Robinson, the unarmed biracial teen killed in March by police in Madison, Wisconsin deserved to die, some members of the public have boldly told his family. Other have suggested that perhaps if the 19-year-old wasn’t intoxicated and physically violent, Officer Matt Kenny would not have used lethal force.

Andrea Irwin, Robinson’s mother, has previously tweeted that she wasn’t letting the hateful and insensitive words get to her. But early Tuesday morning, she had had enough, tweeting her frustration with people who seem intent on making her deceased son a villain and the white officer a hero.

Police have said Robinson, who was under the influence of several drugs at the time of his encounter with Kenny, physically assaulted the officer March 6 before he was shot multiple times in the face, chest and arm. Friends who were aware that Robinson had taken drugs called police after he reportedly assaulted someone in an apartment on Williamson Street.

Some of these details came to light in a state Department of Criminal Investigations probe of the shooting, which Irwin believed was a deliberate attempt by some officials to make her son less sympathetic.

“They’ve gone above and beyond to try to make sure they kick me when I’m down,” Irwin told CNN’s Anderson Cooper last week. “They have done a smear campaign against my child.” Irwin, who is Caucasian, has not shied away from suggesting that her son’s mixed race – he was half African-American – played a role in how Kenny perceived Robinson.

Following months of national protests over the police-involved killings of unarmed black men, Robinson’s death also drew attention to Madison’s racial disparities. Black youth in Dane County, where Robinson resided and where the state capitol sits, are six times more likely to be arrested than white youth, according to the Wisconsin State Journal. Three-quarters of the black youths live in poverty versus just 5 percent of whites.

Irwin, who has three remaining children, has publicly mourned Robinson’s death. She has done multiple national TV appearances to talk about the personal tragedy. But it’s her Twitter presence that appears to attract the hateful words. “Please take care and don't let horrible folks on Twitter upset you,” one supporter tweeted to Irwin May 17. Irwin replied May 18, “They do not move me at all”