Nhan—who has authored a book entitled Issues and Controversies in Policing Today—contends that police training in the United States hasn't changed much over the years.
Nhan acknowledges that policing is inherently dangerous, but offers that officers tend to go into situations feeling their lives are constantly in danger.
In the Jefferson incident, police had arrived to a residence in response to a call of an open door at a late hour and during the encounter, arriving officers circled the house with their guns drawn.
Jefferson reportedly picked up a pistol after she heard noises outside, and when she came in contact with officers, Dean fired a single fatal shot.
Nhan compared Jefferson's death to the September 2018 shooting of Botham Jean in Dallas, when former Dallas Police Department Officer Amber Guyger shot and killed the 26-year-old man in his own apartment, mistakenly thinking it was her own.
Dean resigned from Fort Worth PD earlier this week, and Guyger was sentenced to 10 years in prison last week.