"The implication of the term suggests an inherent weakness or deficiency on the part of the road user labeled as vulnerable and this may limit consideration of other factors that may have caused their increase in risk exposure, such as the behavior of other road users or poor infrastructure."
@inliuofjoan great question! So there are actually differing definitions of “VRU” in statutes. Older definitions included motorcyclists and may have included older drivers as well. I should check! More recent one that I deal with in FHWA relevant statute is just peds/bikes/scooters/equine