Seems pretty straightforward to me.

 

The ACLU and other civil rights organizations are calling for an investigation. As far as I can see, the story is pretty simple. I really don't know what needs investigating.

 

October 25, Texas State Troopers tried to pull over a pickup they suspected of carrying illegal drugs. The truck fled. A department helicopter was called to assist in the chase. One of the tactical flight officers, Miguel Avila, fired his weapon to disable the pickup. Two people in the pickup were killed.

 

As it turns out, the pickup was not carrying illegal drugs. It was carrying illegal aliens from Guatemala. Either way, it appears to me the officer was justified in stopping the fleeing lawbreakers.

 

"ACLU seeks probe of killings by trooper." The Dallas Morning News; November 2, 2012; p. 4A.