This guy was highly irresponsible in how he approached this situation and from what I observed was trying to get a reaction from the Police. He put his dog in that situation, failed to properly secure his dog before approaching the Officers, and owns part of the responsibility for his dogs death.
On the other hand, why was this guy detained and placed into handcuffs? For videotaping? From what I saw this was all senseless and resulted in the unecessary death of Max. This video was extremely sickening.
The cops are just going to have to get used to living in a world where everything they do is videotaped, either by ubiquitous security cameras owned by the government and private citizens or by people carrying cameras on themselves and in their cars. Then they will have to start recording everything they do if for no other reason than to have a defense against creative editing by other camera owners.
Also be on the lookout for laws which require cameras to automatically shut down based on either a radio or optical signal so police can create blackout zones where they can't be observed. Better save some of today's cameras so you have something without any such new feature.