According to a 2023 report from the nonprofit Violence Policy Center, the rate of murders committed by men against women in the United States fell between 1996 and 2014, when around 1.1 out of every 100,000 women were killed. But it began increasing in 2015, with a sharper uptick during the pandemic, when lockdowns kept many women at home with their abusers, reaching a rate of 1.3 per 100,000 women in 2020. The vast majority of those women knew the men who killed them, the report said, and most of them had been in intimate partnerships.

Mr. Simpson’s trial rocked the nation in the 1990s. Before her death, Ms. Brown Simpson had tried to get the police to intervene multiple times, but they rarely took substantive action. In 1989, officers found her badly beaten and arrested Mr. Simpson. He was convicted of spousal abuse, but was let off with a fine and probation. The couple divorced in 1992, two years before Ms. Brown Simpson’s death. But in October 1993, Ms. Brown Simpson called 911, saying, “He’s back.” In June 1994, she was killed.

The Simpson case came at a time when attempts to raise awareness about domestic violence were already gaining traction, said Emily Sack, an expert on domestic violence at the Roger Williams University School of Law.

Mr. Simpson’s acquittal in the criminal trial was viewed by supporters of victims as a setback, but it also caused a powerful backlash that helped change public perception around domestic violence, Ms. Sack said.

Shortly after Ms. Brown Simpson’s death, the Violence Against Women Act gained final approval in Congress and became law, and her sister, Denise Brown, helped save it from budget cuts the following year. In recent years, some states have broadened their definitions of abuse, incorporating things like identity theft and the notion of coercive control, a form of manipulation that can be more subtle than physical abuse, into their legal definitions of domestic violence.