I live in a rural county where there are no leash laws. Many people let their dogs roam all day and night. We have a chain-link fenced area for our 4 ankle-bitters and the only time they are outside of that fence is when they go, on leashes, on their daily (usually) walk. The fence is also for their protection, as Chihuahuas, Chi mix and Yorkies have little-man syndrome and won't back down from big dogs. We also have coyotes, foxes, raccoons, skunks, owls, hawks, etc. that will go after small dogs. Even deer have been known to kick or stomp a small dog.
It looks like she is in more of a urban or residential area and if so, it would be surprising to me if there are no leash laws in place.....but we all know how some people regard some laws if they don't agree with them...