When the world saw the video of George Floyd taking his last breath under the knee of a police officer while onlookers pleaded for his life, the outrage was universal.

Republicans and Democrats agreed it was horrific, as did police chiefs and rank-and-file officers, and protesters of every race in towns large and small.

“It is important to recognize that everyone should be on the same side of this,” Ben Shapiro, the prominent conservative commentator, said back then, adding, “It’s police brutality, obviously.” In a televised trial, the officer, Derek Chauvin, was convicted of murder and sentenced to 22.5 years in prison.

Five years later, that consensus has disintegrated. The right-wing reshaping of the narrative of that day is in full swing, to the point where Mr. Shapiro is calling on President Trump to pardon Mr. Chauvin.

In the right’s retelling, Mr. Floyd did not die from being deprived of air, and Mr. Chauvin was railroaded by a country that flew into a panic over race and did not consider the facts soberly. To build this case, conservatives have packaged misleading details from court documents, images of burning and looting during the protests, Mr. Floyd’s criminal record and drug use, and legal theories that lawyers say are distorted.

Disputing facts that most people once agreed on has become part of a new political playbook, often employed by right-leaning pundits and politicians. But the killing of George Floyd on May 25, 2020 was not just any news story. For conservatives, it was the catalyst for a kind of liberal mania that, some of them assert, led directly to racial hiring quotas, “woke” curriculums in school and white guilt.