I've been wondering about the costume and how the murderer acquired it and got rid of it. I've thought about it a lot- here is what I've come up with the help from everyone who has posted about the outfit.
It's been said by some that this costume was sort of cobbled together and not real SWAT gear. Many people have access to black pants- they could be sweat pants, scrubs, or even some type of pants from a martial arts or karate-style workout. Black shirts are also easy to come by. Now lets say the murderer had easy access to knee pads, padding, and a black vest- the type you'd use in self-protection courses. Add in a balaklava, which are used in the same type of courses during the role-play portion.... Ex-military often have these, too. As for footwear- black combat boots or black rain boots. Now you need some gloves- easy to come by and most people even in TX require gloves at some point during the winter. These items are all ones that could easily be brought back home after the murder, washed and put back where they belong with no one the wiser.
Now we're left with a black helmet and the POLICE patch. As for the helmet- It's been speculated that it's anything from a bike helmet to a baseball helmet (softball batting helmet, perhaps) or a motorcycle helmet. This is going to be one thing that is hard to hide. I wouldn't be surprised if this is something that the perp ditched somewhere or has hidden on purpose or in plain sight. The POLICE patch would be easy to hide also- say it just attaches to a vest with Velcro. That means it can be folded up and hidden under a piece of furniture, in a drawer, taped inside a cabinet, or simply thrown in the trash.
. Google Markia Benson, who was recently killed in a horrific manner, and there's been practical radio silence. (Disclaimer: searchable social media also plays a role). 
