Following the death of a New York City police officer in a friendly fire incident, the NYPD decided to give all police officers a refresher course in an effort to avoid similar tragedies in the future.

As part of the training, officers are being shown a video in which plainclothes cops interact with uniformed officers. Police say they will continue to show the video until all members of the force have viewed it. They also say a new training video is in production.

Despite the steps being taken by the NYPD to prevent friendly fire incidents, like the one that claimed the life of Officer Omar Edwards last week, some retired officers believe race still plays a role in real-life situations.

"There [have] been over 30 African-American officers shot and killed in the line of duty, many times in the back by white officers, and that has never happened in reverse," says Noel Leader, of 100 Blacks in Law Enforcement.

Edwards, who was black, was fatally shot by a white undercover officer in East Harlem while pursuing a suspect who allegedly broke into his car.