Fact check: Trump criticized a criminal justice initiative started by Harris and distorted Biden’s positions.

President Trump, speaking in Pennsylvania on Thursday afternoon, made a litany of accusations against the Democratic nominee, Joseph R. Biden Jr., and his running mate, Senator Kamala Harris of California.

Mr. Trump said that Ms. Harris, during her time as San Francisco’s district attorney, “put a drug-dealing illegal alien into a jobs program instead of into prison. Four months later, the illegal alien robbed a 29-year old woman, mowed her down with an SUV, fracturing her skull and ruining her life.”

The attack was an echo of the Willie Horton episode during the 1988 presidential race between former President George Bush and Gov. Michael S. Dukakis of Massachusetts. In that race, Mr. Bush’s campaign and its allies repeatedly invoked Mr. Horton, a Black prisoner in Massachusetts who, while released on a furlough program, raped a white woman, to suggest Mr. Dukakis was soft on crime. Mr. Dukakis did not start the furlough program, but supported it.

Mr. Trump was referring to the case of Alex Izaguirre, an undocumented immigrant convicted of selling cocaine in 2008. He was a participant in Back on Track, an initiative spearheaded by Ms. Harris that placed young first-time drug offenders who pleaded guilty to their crimes into a jobs program rather than jail.