What year are these cars?

I think the car on the left is a Chevrolet, the one after the gap is a Pontiac, the next two I can't tell for sure.

Thanks!

My best guess is that those cars are 1930s Pontiacs, judging from their style and the shapes of their trunk emblems. The men on the roof look like national guardsmen, so perhaps the photo dates to the 1939 strike.