Amy Forliti, Steve Karnowski And Tammy Webber In this image from video, Minneapolis Police Officer Nicole Mackenzie testifies as Hennepin County Judge Peter Cahill presides, Tuesday, April 13, 2021, in the trial of former Minneapolis police Officer Derek Chauvin at the Hennepin County Courthouse in Minneapolis, Minn. Chauvin is charged in the May 25, 2020 death of George Floyd. (Court TV via AP, Pool) April 13, 2021 - 2:37 PM MINNEAPOLIS - Former Officer Derek Chauvin was justified in pinning George Floyd to the ground because he kept struggling, a use-of-force expert testified for the defence Tuesday, contradicting a parade of authorities from both inside and outside the Minneapolis Police Department.