Just weeks after Chicago police officer Jason Van Dyke was charged with first-degree murder in the shooting death of Laquan McDonald, local officials have announced their decision to not charge another officer in the shooting death of 25-year-old Ronald Johnson III. Police say that Johnson pointed a gun at them before officer George Hernandez shot him in the back, reports the Associated Press. Grainy dashcam footage was promptly shown during a news conference held by Assistant State’s Attorney Lynn McCarthy, with McCarthy slowing down the video to show what she claims is a "semiautomatic pistol with 12 live rounds loaded" in Johnson's possession. The video, which has no audio, has spurred additional controversy surrounding an oft-repeated theory that officers might have intentionally "switched off" the audio to conceal damning evidence. According to McCarthy, however, officers repeatedly commanded Johnson to drop his weapon.

These findings come in the wake of an impending Department of Justice investigation into the practices of the Chicago Police Department, particularly in the wake of the Laquan McDonald shooting and allegations of a purported cover-up. "What we are looking at is whether or not the police department has engaged in unconstitutional policing," U.S. Attorney General Loretta Lynch​ told reporters when announcing the decision to open a civil rights probe into the department. In a statement obtained by ABC News, Chicago Mayor Rahm Emanuel expressed his support of the investigation:

Our mutual goal is to create a stronger, better police department that keeps the community safe while respecting the civil rights of every Chicagoan. Nothing is more important to me than the safety and well-being of our residents and ensuring that the men and women of our police department have the tools, resources and training they need to be effective crime fighters, stay safe, and build community trust.

Earlier this month, Emanuel called for the resignation of Chicago Police Department Superintendent Garry McCarthy. "At this point and at this juncture in the city, given what we are working on, he has become an issue rather than dealing with the issues," Emanuel said. Of course, Emanuel has faced his own barrage of criticism in the wake of the department's handling of the death of Laquan McDonald in light of the nation's increasingly renewed focus on recognizing and ending the prevalence of police brutality in Chicago and beyond.

As for the legalities behind shooting a reportedly fleeing suspect (Ronald Johnson III), PBS breaks down what the law actually says:

Only in very narrow circumstances. A seminal 1985 Supreme Court case, Tennessee vs. Garner, held that the police may not shoot at a fleeing person unless the officer reasonably believes that the individual poses a significant physical danger to the officer or others in the community. That means officers are expected to take other, less-deadly action during a foot or car pursuit unless the person being chased is seen as an immediate safety risk.

In other words, a police officer who fires at a fleeing man who a moment earlier murdered a convenience store clerk may have reasonable grounds to argue that the shooting was justified. But if that same robber never fired his own weapon, the officer would likely have a much harder argument.

As previously reported, 2015 has been an unsettling year for police-involved shooting deaths. Per the Guardian's ongoing The Counted project, police have killed 1,051 people in the United States this year alone.