In criminal law, mens rea is the mental state of a defendant who is accused of committing a crime. In common law jurisdictions, most crimes require proof both of mens rea and actus reus before the defendant can be found guilty.
In law, a reasonable person, reasonable man, sometimes referred to situationally, is a hypothetical person whose character and care conduct, under any common set of facts, is decided through reasoning of good practice or policy. It is a legal fiction crafted by the courts and communicated through case law and jury instructions. In some practices, for circumstances arising from an uncommon set of facts, this person represents a composite of a relevant community's judgement as to how a typical member of that community should behave in situations that might pose a threat of harm to the public.
In criminal procedure law of the United States, an exigent circumstance allows law enforcement to enter a structure without a search warrant, or if they have a "knock and announce" warrant, allows them to enter without knocking and waiting for the owner's permission to enter. It must be a situation where people are in imminent danger, evidence faces imminent destruction, or a suspect's escape is imminent. Once entry is obtained, the plain view doctrine applies, allowing the seizure of any evidence or contraband discovered in the course of actions consequent upon the exigent circumstances.
The open-fields doctrine, in the U.S. law of criminal procedure, is the legal doctrine that a "warrantless search of the area outside a property owner's curtilage" does not violate the Fourth Amendment to the United States Constitution. However, "unless there is some other legal basis for the search," such a search "must exclude the home and any adjoining land that is within an enclosure or otherwise protected from public scrutiny."
In law, willful ignorance is when a person seeks to avoid civil or criminal liability for a wrongful act by intentionally keeping themselves unaware of facts that would render them liable or implicated. In United States v. Jewell, the court held that proof of willful ignorance satisfied the requirement of knowledge as to criminal possession and importation of drugs.
Cheek v. United States, 498 U.S. 192 (1991), was a United States Supreme Court case in which the Court reversed the conviction of John L. Cheek, a tax protester, for willful failure to file tax returns and tax evasion, who was convicted again during retrial. The Court held that an actual good-faith belief that one is not violating the tax law, based on a misunderstanding caused by the complexity of the tax law, negates willfulness, even if that belief is irrational or unreasonable. The Court also ruled that an actual belief that the tax law is invalid or unconstitutional is not a good faith belief based on a misunderstanding caused by the complexity of the tax law, and is not a defense.
In English criminal law, intention is one of the types of mens rea that, when accompanied by an actus reus, constitutes a crime.
In United States v. Oakland Cannabis Buyers' Cooperative, 532 U.S. 483 (2001), the United States Supreme Court rejected the common-law medical necessity defense to crimes enacted under the federal Controlled Substances Act of 1970, regardless of their legal status under the laws of states such as California that recognize a medical use for marijuana. Oakland Cannabis Buyers' Cooperative was represented by Gerald Uelmen.
Dennis G. Jacobs is a senior United States circuit judge of the United States Court of Appeals for the Second Circuit.
The Fifth Amendment to the United States Constitution creates several constitutional rights, limiting governmental powers focusing on criminal procedures. It was ratified, along with nine other amendments, in 1791 as part of the Bill of Rights.
United States v. Weitzenhoff, 35 F.3d 1275 is a legal opinion from the Ninth Circuit Court of Appeals that addresses the confusing mens rea requirement of a federal environmental law that imposed criminal sanctions on certain polluters. The main significance of the court's opinion was that it interpreted the word "knowingly" in the statute to mean a general awareness of the wrongfulness of one's actions or the likelihood of illegality, rather than an actual knowledge of the statute being violated. Circuit Court Judge Betty Binns Fletcher authored the majority's legal opinion in this case.
In the North American legal system and in US Occupational Safety and Health Administration regulations, willful violation or willful non-compliance is a violation of workplace rules and policies that occurs either deliberately or as a result of neglect.
United States v. Dougherty, 473 F.2d 1113 was a 1972 decision by the United States Court of Appeals for the District of Columbia in which the court ruled that members of the D.C. Nine, who had broken into Dow Chemical Company, vandalized office furniture and equipment, and spilled about a bloodlike substance, were not entitled to a new trial on the basis of the judge's failing to allow a jury nullification jury instruction. The Appeals Court ruled, by a 2–1 vote:
The fact that there is widespread existence of the jury's prerogative, and approval of its existence as a "necessary counter to casehardened judges and arbitrary prosecutors," does not establish as an imperative that the jury must be informed by the judge of that power. On the contrary, it is pragmatically useful to structure instructions in such wise that the jury must feel strongly about the values involved in the case, so strongly that it must itself identify the case as establishing a call of high conscience, and must independently initiate and undertake an act in contravention of the established instructions. This requirement of independent jury conception confines the happening of the lawless jury to the occasional instance that does not violate, and viewed as an exception may even enhance, the over-all normative effect of the rule of law. An explicit instruction to a jury conveys an implied approval that runs the risk of degrading the legal structure requisite for true freedom, for an ordered liberty that protects against anarchy as well as tyranny.
Aiding and abetting is a legal doctrine related to the guilt of someone who aids or abets another person in the commission of a crime. It exists in a number of different countries and generally allows a court to pronounce someone guilty for aiding and abetting in a crime even if he or she is not the principal offender. The words aiding, abetting and accessory are closely used but have differences. While aiding means providing support or assistance to someone, abetting means encouraging someone else to commit a crime. Accessory is someone who in fact assists "commission of a crime committed primarily by someone else". However, some jurisdictions have merged being an accessory before the fact with aiding and abetting.
Schmuck v. United States, 489 U.S. 705 (1989), is a United States Supreme Court decision on criminal law and procedure. By a 5–4 margin it upheld the mail fraud conviction of an Illinois man and resolved a conflict among the appellate circuits over which test to use to determine if a defendant was entitled to a jury instruction allowing conviction on a lesser included charge. Justice Harry Blackmun wrote for the majority; Antonin Scalia for the dissent.
United States v. Watson, 423 U.S. 411 (1976), was a case decided by the Supreme Court of the United States that decided that a warrantless arrest in public and consenting to a vehicle search did not violate the Fourth Amendment.
Walker Process Equipment, Inc. v. Food Machinery & Chemical Corp., 382 U.S. 172 (1965), was a 1965 decision of the United States Supreme Court that held, for the first time, that enforcement of a fraudulently procured patent violated the antitrust laws and provided a basis for a claim of treble damages if it caused a substantial anticompetitive effect.
McFadden v. United States, 576 U.S. 186 (2015), was a United States Supreme Court case in which the Court held that section 841 of the Controlled Substances Act requires the government to prove that to be in criminal violation, a defendant must be aware that an analogue defined by the Controlled Substance Analogue Enforcement Act with which he was dealing was a controlled substance.
United States v. Giovanetti, 919 F.2d 1223, is a criminal case that interpreted the jury instruction known as the ostrich instruction, that willful ignorance counted as knowledge where required for a guilty mind in complicity to commit a crime. The court held that willful ignorance required a positive act to avoid knowledge, otherwise it reduces the mens rea requirement of proving "knowledge" to merely proving "negligence".
Two main questions arise in the law surrounding driving after having ingested cannabis: (1) whether cannabis actually impairs driving ability, and (2) whether the common practice of testing for THC is a reliable means to measure impairment. On the first question, studies are mixed. Several recent, extensive studies–including one conducted by the National Highway Traffic Safety Administration and one conducted by the American Automobile Association (AAA)–show that drivers with detectable THC in their blood are no more likely to cause car crashes than drivers with no amount of THC in their blood. Others show that cannabis can impair certain abilities important to safe driving –but no studies have been able to show that this increases the actual risk of crashing, or that drivers with THC in their blood cause a disproportionate number of crashes. On the second question, the studies that have been conducted so far have consistently found that THC blood levels and degree of impairment are not closely related. No known relationship between blood levels of THC and increased relative crash risk, or THC blood levels and level of driving impairment, has been shown by single-crash or classic-control studies. Thus, even though it is possible that cannabis impairs driving ability to some extent, there are currently no reliable means to test or measure whether a driver was actually impaired.
