You can see it coming from a mile away, but apparently this police officer was momentarily blind to the danger.

Tap the video above to watch how not to fire a gun.

In what can only be described as an inexplicable lapse in judgement, a woman wearing a Brazilian Military Police officer's uniform has been filmed holding her pistol just centimetres away from her face as she prepares for a firing demonstration.

Despite her extensive preparation, while lying in the prone position, the police officer could not change the laws of physics.

After pulling the trigger, the pistol shoots back because of its recoil and hits her in the face.

While the officer received only minor injuries from the incident, she was not able to hide the embarrassment on her face after the gaffe.