[nkurz]

A light might not help you. The police might think that it's a laser sight, and be even more likely to shoot you:

The officers claim that the Taser projected a red light, which they assumed was the laser sight of a handgun, and feared for their lives. At 7.18:43pm, Schiff and Sawyer began barraging Nieto with .40-calibre bullets.

http://www.theguardian.com/us-news/2016/mar/21/death-by-gent...

[bfuller]

Flashlights are also commonly attached to firearms.

In fact, it would be hard to distinguish between someone holding a phone with a light on or someone holding a gun with a light attached.

I'm not defending police brutality, but these are often difficult situations.