You have two friends in a deadly force situation: your gun and your flashlight. Reach for your flashlight first — long before the situation escalates. It may save your life.
If you have even an inkling of an idea that you may be facing danger, reach for your flashlight and shine it in the direction of the perceived threat. The light allows you to clearly see what is going on and determine if the person in front of you is a threat or not. If that person is not a threat, you are only guilty of shining a flashlight on an innocent person. If that person is a threat, he (it’s typically a man) now has to deal with the blinding light and the understanding that he has lost the element of surprise.
If the threat continues, draw your gun and put rounds on target if you need to.
Practice. Practice. Practice.
Use your flashlight in dry-fire training drills. Take your flashlight to the range and practice. Figure out now which hold you prefer: Harries or FBI style. Either will work and I’m not going to debate the idea that the bad guy only has to shoot at your light if you use the Harries hold.
You will never learn new gunfighting skills during a gunfight. Learn them now before the pressure is on.