top rear windshield hazard lights

I notice that modern police cars without roof-mounted light bars use LED lights mounted just inside the rear glass at the top for rear flashers... can this idea be applied to create rear hazard lights for stopped vehicles, integrated into the top of the rear glass - much better distance visibility (height, brightness), and can be set to flashing patterns that stand out better (e.g. alternating-flash dashed yellow strip along the entire width). Considering that many cars already have center brake lights in this location, it is a straightforward extension of that concept.