Consent

• An express consent is one that is clearly and unmistakably stated, rather than implied. It may be given in writing, by speech (orally), or non-verbally, e.g. by a clear gesture such as a nod. Non-written express consent not evidenced by witnesses or an audio or video recording may be disputed if a party denies that it was given.
• Implied consent is consent inferred from a person's actions and the facts and circumstances of a particular situation (or in some cases, by a person's silence or inaction). Some examples include unambiguously soliciting or initiating sexual activity or the implied consent to physical contact by participants in a hockey game or being assaulted in a boxing match.
• Informed consent in medicine is consent given by a person who has a clear appreciation and understanding of the facts, implications, and future consequences of an action. The term is also used in other contexts, such as in social scientific research, when participants are asked to affirm that they understand the research procedure and consent to it, or in sex, where informed consent means each person engaging in sexual activity is aware of any positive statuses (for sexually transmitted infections and/or diseases) they might expose themselves to.
• Unanimous consent, or general consent, by a group of several parties (e.g., an association) is consent given by all parties.
• Substituted consent, or the substituted judgment doctrine, allows a decision maker to attempt to establish the decision an incompetent person would have made if he or she were competent.[3]

The concept of end-user given consent plays an important role in digital regulations such as the European General Data Protection Regulation (GDPR).[4] The GDPR (Article 6) defines a set of different legal bases for lawful processing of personal data. End-users’ consent is only one of these possible bases. However, as a result of the GDPR enforcement (in 2018) and other legal obligations, data controllers (online service providers) have widely developed consent-obtaining mechanisms in recent years.[4] According to the GDPR, end-users' consent should be valid, freely given, specific, informed and active.[4] But the lack of enforceability regarding obtaining lawful consents has been a challenge in the digital world. As an example, a 2020 study, showed that the Big Tech, i.e. Google, Amazon, Facebook, Apple, and Microsoft (GAFAM), use dark patterns in their consent obtaining mechanisms, which raises doubts regarding the lawfulness of the obtained consent.[4]

Consent can be either expressed or implied. For example, participation in a contact sport usually implies consent to a degree of contact with other participants, implicitly agreed and often defined by the rules of the sport.[5] Another specific example is where a boxer cannot complain of being punched on the nose by an opponent; implied consent will be valid where the violence is ordinarily and reasonably to be contemplated as incidental to the sport in question.[6] Express consent exists when there is oral or written agreement, particularly in a contract. For example, businesses may require that persons sign a waiver (called a liability waiver) acknowledging and accepting the hazards of an activity. This proves express consent, and prevents the person from filing a tort lawsuit for unauthorised actions.

In English law, the principle of volenti non fit injuria (Latin: "to a willing person, injury is not done") applies not only to participants in sport, but also to spectators and to any others who willingly engage in activities where there is a risk of injury. Consent has also been used as a defense in cases involving accidental deaths during sex, which occur during sexual bondage. Time (May 23, 1988) referred to this latter example, as the "rough-sex defense". It is not effective in English law in cases of serious injury or death.

As a term of jurisprudence prior provision of consent signifies a possible defence (an excuse or justification) against civil or criminal liability. Defendants who use this defense are arguing that they should not be held liable for a tort or a crime, since the actions in question took place with the plaintiff or "victim's" prior consent and permission.

In medical law, consent is important to protect a medical practitioner from liability for harm to a patient arising from a procedure. There are exemptions, such as when the patient is unable to give consent.[3]

Also, a medical practitioner must explain the significant risks of a procedure or medication (those that might change the patient's mind about whether or not to proceed with the treatment) before the patient can give a binding consent. This was explored in Australia in Rogers v Whitaker.[7] If a practitioner does not explain a material risk that subsequently eventuates, then that is considered negligent.[8] These material risks include the loss of chance of a better result if a more experienced surgeon had performed the procedure.[9] In the UK, a Supreme Court judgment[10] modernized the law on consent and introduced a patient-focused test to UK law: allowing the patient rather than the medical professionals to decide upon the level of risk they wish to take in terms of a particular course of action, given all the information available. This change reflects the Guidance of the General Medical Council on the requirement to consent patients, and removes the rule of medical paternalism.[11]

Social scientists are generally required to obtain informed consent from research participants before asking interview questions or conducting an experiment. Federal law governs social science research that involves human subjects, and tasks institutional review boards (IRBs) at universities, federal or state agencies, and tribal organizations to oversee social science research that involves human subjects and to make decisions about whether or not informed consent is necessary for a social scientific study to go forward. Informed consent in this context generally means explaining the study's purpose to research participants and obtaining a signed or verbal affirmation that the study participants understand the procedures to be used and to consent to participate in the study.[12]^:51–55

Some types of social scientific research, such as psychological experiments, may use deception as part of the study; in these cases, researchers may not fully describe the procedures to participants, and thus participants are not fully informed. However, researchers are required to debrief participants immediately after the experiment is concluded. Certain populations are considered to be vulnerable, and in addition to informed consent, special protections must be made available to them. These include persons who are incarcerated, pregnant women, persons with disabilities, and persons who have a mental disability. Children are considered unable to provide informed consent.[12]^:51–55

Some countries, such as New Zealand with its Resource Management Act and its Building Act, use the term "consent" for the legal process that provide planning permission for developments like subdivisions, bridges or buildings. Achieving permission results in getting "Resource consent" or "Building consent".

In Canada "consent means… the voluntary agreement of the complainant to engage in sexual activity" without abuse or exploitation of "trust, power or authority", coercion or threats.[13] Consent can also be revoked at any moment.[14]

Sexual consent plays an important role in defining what sexual assault is, since sexual activity without consent by all parties is considered rape.[15][16] In the late 1980s, academic Lois Pineau argued that we must move towards a more communicative model of sexuality so that consent becomes more explicit and clear, objective and layered, with a more comprehensive model than "no means no" or "yes means yes".[17] Many universities have instituted campaigns about consent. Creative campaigns with attention-grabbing slogans and images that market consent can be effective tools to raise awareness of campus sexual assault and related issues.[18]

Since the late 1990s, new models of sexual consent have been proposed. Specifically, the development of "yes means yes" and affirmative models, such as Hall's definition: "the voluntary approval of what is done or proposed by another; permission; agreement in opinion or sentiment."[14] Hickman and Muehlenhard state that consent should be "free verbal or nonverbal communication of a feeling of willingness' to engage in sexual activity."[19] Affirmative consent may still be limited since the underlying, individual circumstances surrounding the consent cannot always be acknowledged in the "yes means yes", or in the "no means no", model.[15]

Some individuals are unable to give consent. Children or minors below a certain age, the age of sexual consent in that jurisdiction, are deemed not able to give valid consent by law to sexual acts. Likewise, persons with Alzheimer's disease or similar disabilities may be unable to give legal consent to sexual relations even with their spouse.[20]

Within literature, definitions surrounding consent and how it should be communicated have been contradictory, limited or without consensus.[15][16] Roffee argued that legal definition needs to be universal, so as to avoid confusion in legal decisions. He also demonstrated how the moral notion of consent does not always align with the legal concept. For example, some adult siblings or other family members may voluntarily enter into a relationship, however the legal system still deems this as incestual, and therefore a crime.[21] Roffee argues that the use of particular language in the legislation regarding these familial sexual activities manipulates the reader to view it as immoral and criminal, even if all parties are consenting.[22] Similarly, some children under the legal age of consent may knowingly and willingly choose to be in a sexual relationship. However the law does not view this as legitimate. Whilst there is a necessity for an age of consent, it does not allow for varying levels of awareness and maturity. Here it can be seen how a moral and a legal understanding do not always align.[23]

Initiatives in sex education programs are working towards including and foregrounding topics of and discussions of sexual consent, in primary, high school and college Sex Ed curricula. In the UK, the Personal Social Health and Economic Education Association (PSHEA) is working to produce and introduce Sex Ed lesson plans in British schools that include lessons on "consensual sexual relationships," "the meaning and importance of consent" as well as "rape myths".[24] In U.S., California-Berkeley University has implemented affirmative and continual consent in education and in the school's policies.[25] In Canada, the Ontario government has introduced a revised Sex Ed curriculum to Toronto schools, including new discussions of sex and affirmative consent, healthy relationships and communication.[26]