Washington State, enough said.
If you actually read the applicable statute and case law in the state of Washington, you would see that the State of Washington gives private citizens a great deal of authority to use deadly force to apprehend a felon.
Basically if the old guy told him to stop before shooting, he's in the clear.
In fact, the law on the use of deadly force in the State of Washington is very similar to the laws of Texas.
Do a search for RCW 9A.16.010-050
http://apps.leg.wa.gov/rcw/default.aspx?cite=9A.16
Especially, check out the note at the bottom of the page for RCW 9A.16.040
The reason for that note is related to the USSC decision in Garner v. Tennessee, 471 U.S. 1 (1985)