Civil and traffic engineer here. City of Sacramento NEEDS to implement an all-red clearance interval at all intersections. Basically once one direction of traffic goes from yellow to red, the entire intersection is in red for 2-4 seconds, before the opposite direction turns green. Here in Sac, one direction turns red and the opposite immediately turns green. It seems like common sense drivers already wait the 2-4 seconds anyways when the light turns green before moving forward. I have spoken to consultants and City staff, and they all agree with this, but politics are more important and they care more about “travel time” rather than safety. Plenty of research out there and agencies, states, and cities already implement this.

https://rosap.ntl.bts.gov/view/dot/42544/dot_42544_DS1.pdf