I live in Texas. Specifically, San Antonio.
Cooper would most certainly find himself cooling his heels in the Bexar County Jail.
The thieves would not stop, They had his property.
I don't believe you've correctly interpreted the defense of property law. Just from the responses in this thread you can tell most people believe there wasn't anything reasonable about Cooper's conduct.
The theft occurred at 4:20 in the afternoon, daytime. Would that make a difference according to the Texas law you're relying upon?
Under what circumstances would Cooper have lost a right to use deadly force in defense of his property?
In Texas, Cooper would be dead meat.
Active persuit. He saw them steal and leave with his property and he chased after them.That is the key word, active persuit. Had he lost sight of them and then spotted them lets say an hour later he can not then use deadly force to recover.. This has happened many simmilar times in Texas and as far as I know the store owner was within his rights to recover stolen property. No different than if when waking up from a nap in the middle of the day you see some one stealing your tool box from your backyard. If you see them leave with it you can persue and recover and yes even use deadly force IF any other action would result in your bodily harm. You have the right to confront a thief caught in the act. But, you have to catch them in the act and the property in their possesion. If while chasing the thieves with your tool box and they throw it out the window, you have recovered and can no longer persue them with the threat of deadly force.