You are really missing the point here, we live in the USA, a country where everyone is (supposed to be) considered innocent until proven guilty; everyone must be entitled to their day in court to assure a fair system. Yet, these police acted as judge, jury, and executioner. It has already been established that they were heard on audio saying ''get the gas, let's burn it down''.
What the police did is wrong, you can't defend it, it doesn't matter how many were killed, it is simply not their right in this country to execute a suspect through arson. There are a thousand other ways that they could have handled this situation, the most effective would have simply been to wait it out, he would have eventually ran out of food.
Here's the scary, part once you let something like this be deemed acceptable, what's to say they won't repeat this type of behavior? Maybe next time the suspect will be falsely accused....