Assuming the number of right-angle crashes is proportional to the number of people who run red lights, the reduction due to having a longer yellow light is larger than the reduction due to the RLC. And that's before considering the rear-end collisions, which a red light camera increases but a longer yellow light reduces.
This is interesting, but it seems to mostly be focused on violations rather than crashes. I can see how the two might be related. But I also somewhat suspect that early into red violations may not be the type of red light running that causes accidents the most.
http://saferstreetsla.org/wp-content/uploads/reports/A%20Com...
Assuming the number of right-angle crashes is proportional to the number of people who run red lights, the reduction due to having a longer yellow light is larger than the reduction due to the RLC. And that's before considering the rear-end collisions, which a red light camera increases but a longer yellow light reduces.