What kind of bird of prey i saw today. it was amazing.?

ok the bird i saw which was in a weird location in milwaukee, wi. i was on a bus stop waiting for the bus on 51st st. between capitol dr. & fond du lac ave, by the 'ace hardware store' & i saw a falcon type of bird little bit smaller than a crow. was brown with tan specs on the front, small beak. it wasn't a sparrow.