MBE Rules · Criminal Law
Deadly Weapon Inference
Deadly weapon inference
The rule
Intentional use of a deadly weapon on a vital part of the body permits — but does not compel — an inference of intent to kill; mandatory presumptions of intent violate due process (Sandstrom).
In plain English
The Deadly Weapon Inference allows a jury to assume that if someone intentionally uses a deadly weapon on a vital part of another person's body, they likely intended to kill. However, this inference is not automatic, and the prosecution must still prove intent beyond a reasonable doubt. Additionally, any mandatory presumptions about intent would violate a defendant's due process rights.
Worked example
During a heated argument, John stabs Mike in the chest with a knife, hitting a vital organ. The prosecution argues that this action allows the jury to infer that John intended to kill Mike. The jury finds that while the inference is permissible, they must still consider all evidence before concluding John's intent.
Memory hook
A deadly weapon and a vital target suggest intent, but it's not a guarantee!
The trap
Exams may present scenarios where students assume intent simply because a deadly weapon was used, overlooking the need for a thorough analysis of the evidence. Students might also confuse permissible inferences with mandatory presumptions.
How examiners test it
Questions often involve fact patterns where a defendant uses a deadly weapon, prompting students to analyze whether the circumstances support an inference of intent to kill. Look for nuances in how the weapon was used and the context of the act.
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