"...we find that the January 2025 implementation of congestion pricing reduced passenger vehicle traffic by roughly 21 percent near the boundary and improved total EMS travel times by 63–70 seconds, approximately 5–6 percent. Effects emerged quickly and show little evidence of displacement to adjacent areas... These findings suggest that cost-benefit analyses of congestion pricing systematically understate net social benefits by omitting emergency response improvements."

https://www.nber.org/papers/w35414