When teenager Laquan McDonald was killed in a police encounter, police accounts indicated that the youth was acting strangely and lunged at police with a knife, forcing the officer to fire.

Dash cam footage which was court-ordered to be released after Officer Jason Van Dyke was charged with first-degree murder paints a different picture of a teen walking away from officers, clearly not lunging or behaving in a way that would make officers fear for their lives.

Van Dyke released 16 rounds of ammo at the teen, his shooting lasting for nearly 15 seconds, even as McDonald lay dead on the ground.

If it weren’t for this video, Van Dyke might have gotten away with what is clearly excessive and unprovoked murder.

What does it tell us that a police report and the actual video evidence are so vastly different? How, in the face of such clear dishonesty, can we do anything but demand that dash and body cams be required on all police officers at all times?

Most officers may be honest and trustworthy, but transparency is required when dealing with such serious issues. If we cannot guarantee an honest account from the officers themselves, we must obtain it in other ways.

Read more at The Huffington Post.