Mating flies apparently don’t mind if you stick a camera in their faces. I believe these are Flesh Flies- according to Field Guide to Insects and Spiders of North America by Arthur V. Evans, Flesh Flies have a gray and black checkerboard pattern on their abdomen, clear wings, and black legs. With 20,000 species of flies in the United States and Canada, I’m just happy if my ID is somewhere in the ballpark.
There were actually a bunch of these flies near my backyard fence. I’m not sure if they had just became adults and had emerged all at once.