An injured person making a legal claim for compensation must prove that another party was negligent. Negligence is a failure to act as a reasonably careful person would under the circumstances.
Consider an auto accident. The concept of negligent is broader than merely driving according to the legal rules of the road—obeying the speed limit, traffic signals, etc. If there are inclement weather conditions and/or heavy traffic conditions, a reasonably careful driver would slow down. Merely obeying the posted speed limit is not reasonably careful under those circumstances.
It is generally on the person claiming personal injury to prove negligence on the part of another. There are occasionally narrow exceptions under which negligence will be inferred by law under a doctrine called res ipsa loquitur, which is legal Latin meaning something that speaks for itself.
The “speaks for itself” rule may be applied if the accident or occurrence would not ordinarily happen unless someone was negligent, the thing that caused the injury was under the exclusive control of the other party, and the injured party was not negligent.
Washington courts have applied the res ipsa loquitur doctrine:
- when a painter was injured in a fall when the timber broke in the scaffolding erected by the defendant;
- when a scalpel blade dislodged from its handle and was left inside the patient’s body;
- when a box fell from above the customer’s head at a kitchen counter display in a retail store;
- when a dock on which the injured party was walking collapsed beneath her. 
Proving someone was at fault for an injury is not always simple, even in situations where it seems straightforward. The res ipsa loquitur doctrine is only “sparingly applied, ‘in peculiar and exceptional cases, and only where the facts and the demands of justice make its application essential.” 
Washington courts have even declined to apply the res ipsa loquitur in cases where a person was injured on an escalator. A person injured on an escalator must make at least a prima facie case of negligence.
If you believe someone else is responsible for your injury you should speak to a personal injury attorney.
 See Washington Pattern Jury Instruction 10.01.
 Pacheco v. Ames, 149 Wn.2d 431, 436, 69 P.3d 324 (2003);
 Penson v. Inland Empire Paper Co., 73 Wash. 338, 346, 132 P. 39 (1913).
 Ripley v. Lanzer, 152 Wn. App. 296, 307, 215 P.3d 1020 (2009).
 Lemcke v. Lowe’s, unpublished opinion (No. 65849-2-I July 25, 2011).
 Curtis v. Lien, 169 Wn.2d 884, 239 P.3d 1078 (2009).
 Tinder v. Nordstrom, Inc., 84 Wn. App. 787, 792, 929 P.2d 1209 (1997) (quoting Morner v. Union Pac. R.R. Co., 31 Wn.2d 282, 293, 196 P.2d 744 (1948)).
 Tinder v. Nordstrom.
 Knutson v. Macy’s, 1 Wn. App. 2d 543 (2017).