MBE Rules · Torts
Res ipsa loquitur
The rule
Permits inference of breach if (1) the accident is one that ordinarily does not occur without negligence, (2) the instrumentality was in defendant's exclusive control, AND (3) plaintiff did not contribute to the harm. Modern jurisdictions allow circumstantial proof of the elements.
In plain English
If something bad happens that usually doesn't happen without someone's mistake, and the thing causing the harm was only in one person's control, you can assume that person was careless.
Worked example
A sign falls off a building and hits a passerby. The building owner was the only one responsible for maintaining the sign, and the passerby did nothing wrong. We can assume the owner was negligent.
Memory hook
Res Ipsa: Silence Speaks Volumes. When accidents whisper blame, look for exclusive control and no plaintiff fault.
The trap
Students think: Any accident implies negligence. Wrong, because the instrumentality must be in defendant's exclusive control. The actual test is all three elements must be met.
How examiners test it
MBE loves: falling objects or surgical errors. Trap: assuming res ipsa applies without exclusive control. Watch for shared control or plaintiff's contribution.
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