Chauvin was occupied with a hostile crowd when Floyd took his last breath, making it difficult to perform CPR, Nelson said.

It is written in the Minneapolis Police Department to stop CPR when it is no longer safe to perform it, Nelson said, citing the testimony by Minneapolis Police Officer Nicole Mackenzie, the department's medical support officer, who discussed the difficulty of performing CPR in hostile environments.

"She described how it's incredibly difficult to perform EMS efforts in a loud crowd, difficult to focus when you don't feel safe, makes it more difficult to assess a patient and makes it more likely you can miss signs that a patient is experiencing something," Nelson said. "So the distraction, she said, can actually do harm to a patient."

Chauvin would have been paying attention to the behavior of the crowd surrounding him and the other officers while restraining Floyd, Nelson said.

Minnesota Police Department training includes tactics on how to deal with a crowd, especially to "never underestimate a crowd."

"Crowds are very dynamic creatures and can change rapidly," Nelson said.

The bystanders on the scene of the Cup Foods began to raise their voices and call Chauvin names as the incident went on, Nelson said.

How Chauvin interacted with a crowd is in line with how a reasonable police officer would act, Nelson said.

The 9-minute and 29-second cellphone video of Chauvin kneeling on Floyd "completely disregards" what happened leading up to the restraint, Nelson said.

While the prosecution has been focusing on the length of the cellphone video, "a reasonable police officer would have taken into consideration the previous 16 minutes and 59 seconds," which included Floyd's resistance, Nelson said.

"Human behavior is unpredictable, and nobody knows it better than a police officer," Nelson said. "Someone can be compliant one second and fighting the next. Someone can be fighting and then compliant."

Government buildings in downtown Minneapolis are being fortified in the event of unrest following a verdict in the Chauvin trial.

The jury reached a verdict in the trial after deliberating for 4 hours on Monday and 6.5 hours on Tuesday.