TexasCHLforum.com

I would point out that deadly force would be authorized under Texas law for that incident. I don't know Arizona law, of course, and their might be different. People are reporting it that he had shoplifted, which is theft. But when he pulled the knife on the loss prevention officer, it becomes aggravated robbery. Robbery is any theft or attempted theft where force is used to commit the theft or to flee after the theft.

The officer is wrong based on the Garner v. Tennessee and Graham v. Connor decisions. But remember that non-officers do not have to worry about those two decisions, just police officers.