It is no doubt accurate to say that the bar of this state has heretofore assumed (and justifiably so, in view of prior decisions of the court) that, generally speaking, a specific charge of negligence (e.g. excessive speed) may not be established by proof of prior or similar acts of negligence, nor even by proof of customary or habitual negligence of the same sort. Consequently, the opinion of the Washington Supreme Court in Sheddy v. Inland Motor Freight, is of more than passing interest.
Judson F. Falknor,
Competency of Proof of "Customary" Negligence in Support of Charge of Specific Act of Negligence,
12 Wash. L. Rev. & St. B.J.
Available at: https://digitalcommons.law.uw.edu/wlr/vol12/iss1/5