I didn't bother to bring my gun, as I figured I wouldn't be gone long anyway.

When I had nearly made the loop, Mars was hollering at me from his wheelchair for me to hurring and come back. I made my way back, and he wheeled back in the apt and asked me to lock the door. Apparently, three unmarked police cars entered the complex, and went to a nearby building to issue a warrant. The guy didn't care to go, so he climbed down from his third floor balcony and started running, and the chase was on.
Mars was worried that I could have been taken hostage, and knew I would have a more difficult time without my gun. Even though my gun wasn't far away, you usually don't have time to run home and get it when you need it NOW, especially with a miniature schnauzer in tow that likes to sniff everything along the way.
This was unwise on my part; thought I'd share my lesson as a reminder.