cyclists getting clipped by a vehicle turning right is a way too common event. The "right hook" is something that all cyclists must be vigilant in avoiding. most drivers once they pull up to a red light (or yellow) do not check their right mirror before turning. If a bike is there, or coming up along side cars waiting for the light, whamo.
careful out there.
maybe I misunderstood your description of how it went down but it doesnt sound as if the bus driver was driving recklessly or unlawfully.
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2010 Kestrel RT900SL, 800k carbon, chorus/record, speedplay, zonda
2000 litespeed Unicoi Ti, XTR,XT, Campy crank, time atac, carbon forks