Written by attorneys · grounded in primary & secondary sources — see below
2 senses
1
deed or conduct
A voluntary bodily movement or omission that produces an effect in the external world. Criminal and tort liability require such an act paired with the requisite mental state or intent.
2
statute or legislation
A formal written law enacted by a legislative body. Such an act carries the force of law once properly passed and signed.
Each sense below has its own examples, sources, and questions.
Sense 1
1
deed or conduct
A voluntary bodily movement or omission that produces an effect in the external world. Criminal and tort liability require such an act paired with the requisite mental state or intent.
Sources & Authorities· 2 primary sources
Select any source to read its text and confirm it supports the definition.
Model Codes
Common Law
Sense 2
2
statute or legislation
A formal written law enacted by a legislative body. Such an act carries the force of law once properly passed and signed.
Sources & Authorities· 1 primary source
Select any source to read its text and confirm it supports the definition.
Adam Anderson fires a gun during a heated argument with a neighbor. The bullet strikes and kills the neighbor. The shooting constitutes the unlawful act that supports involuntary manslaughter liability under the common-law unlawful-act theory.
Risk Passes on Contract
Albert Allen signs a binding contract to buy land from Atlas Ventures. The signing is the voluntary act that triggers equitable conversion. Before closing a fire destroys the house. Under equitable conversion Albert bears the risk of loss and must still pay the full purchase price.
Duty to Waive Service
Ava Adebayo sues Apollo Energy and sends a proper notice requesting waiver of service. The act of commencing suit and requesting waiver triggers Apollo Energy's duty to avoid unnecessary service expenses by waiving formal service of the summons.
Character Evidence by Opinion
Amelia Amari offers testimony from a coworker that Alexis Archer has a reputation for honesty. The act of offering the opinion character evidence permits the court on cross-examination to inquire into specific instances of Alexis's prior conduct.
Voluntary Act Required
Angela Acosta is charged with theft after items are found in her bag. She cannot be convicted unless the prosecution proves her liability rests on a voluntary act or a legally required omission she was physically capable of performing.
Frequently Asked3
What distinguishes an act from a mere omission in criminal law?+
An act requires a voluntary bodily movement. An omission supports liability only when the defendant had a legal duty to act and was physically capable of performing the required act.
Supporting sources
Does every unlawful act automatically produce involuntary manslaughter at common law?+
No. The unlawful act must cause the death. Only certain felonies or misdemeanors that create a foreseeable risk of death qualify under the unlawful-act theory.
Supporting sources
How does the term act differ when used to describe legislation versus conduct?+
When referring to legislation an act is a formal enacted statute. When referring to conduct an act is a voluntary bodily movement or deed that can trigger tort or criminal liability.
Supporting sources
1
Executive Power Vested
Congress passes a statute limiting the President's removal power over certain officers. The statute cannot override the vesting of executive power in the President under Article II Section 1.
5 U.S. (1 Cranch) 137 (1803)Property
…peremptorily the performance of certain acts on which rights of individuals depend, the officer is amenable to law for his conduct. The heads of departments acting as mere organs of Executive will in political matters are not subject to judicial control but where a specific duty is assigned by law and individual rights…