The charges probably were the result of brandishing a pistol. I'm not up on all the state laws regarding brandishing but in this state it's a gross misdemeanor.
Nothing in our state law about using a light on a pistol. I have one on my P-30 LEM in my night stand and would use it to investigate any disturbance in my house. Outside I would use another light that would be good for 50 yards. Did that not long ago when my wife woke me up and said she heard someone at the front door. Nobody there.(1) It shall be unlawful for any person to carry, exhibit, display, or draw a firearm or weapon in a manner that either manifests an intent to intimidate another or that warrants alarm for the safety of other persons. (2) Any person violating this law above shall be guilty of a gross misdemeanor. If any person is convicted of a violation of this law, the person shall lose his or her concealed pistol license. The court shall send notice of the revocation to the department of licensing, and the city, town, or county which issued the license. Take careful note that a conviction of this crime can result in a permanent deprivation of your 2nd amendment rights.
Putting a light on a pistol doesn't change stupid. That's like trying to turn back the tide.
Great discussion about WML's