In common speech, consent occurs when one person voluntarily agrees to the proposal or desires of another. The concept of consent has been operationalized in several major contexts, including in law, medicine and sexual relationships. Types of consent include implied consent, expressed consent, informed consent and unanimous consent. Consent as understood in legal contexts may differ from the everyday meaning. For example, a person under the legal age of sexual consent may willingly engage in a sexual act, but that consent is not valid in a legal context.
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. 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. 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 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.
The question of consent is important in medical law. For example, a medical practitioner may be liable for harm to a patient by a procedure which was not consented to. There are exemptions, such as when the patient is unable to give consent.
Also, a medical practitioner must explain the significant risks of a procedure (those that might change the patient's mind about whether or not to have it) before the patient can give binding consent. This was explored in Australia in Rogers v. Whitaker (1992) 175 CLR 479. If a practitioner does not explain a material risk that subsequently eventuates, then that is considered negligent. These material risks include the loss of chance of a better result if a more experienced surgeon had performed the procedure.
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. Consent can also be revoked at any moment.
Sexual consent plays an important role in defining what sexual assault is, since sexual activity without consent by all parties is considered rape. 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".
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." Hickman and Muehlenhard state that consent should be "free verbal or nonverbal communication of a feeling of willingness' to engage in sexual activity." 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.
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.
Within literature, definitions surrounding consent and how it should be communicated have been contradictory, limited or without consensus. 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. 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 in all parties are consenting. 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.
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". In U.S., California-Berkeley University has implemented affirmative and continual consent in education and in the school’s policies. 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.
Affirmative consent (explicit yes) is when both parties agree to sexual conduct, either through clear, verbal communication or nonverbal cues or gestures. It involves communication and the active participation of people involved. This is the approach endorsed by colleges and universities in the U.S., who describe consent as an "affirmative, unambiguous, and conscious decision by each participant to engage in mutually agreed-upon sexual activity." According to Yoon-Hendricks, a staff writer for Sex, Etc., "Instead of saying 'no means no,' 'yes means yes' looks at sex as a positive thing." Ongoing consent is sought at all levels of sexual intimacy regardless of the parties' relationship, prior sexual history or current activity ("Grinding on the dance floor is not consent for further sexual activity," a university policy reads). By definition, affirmative consent cannot be given if a person is intoxicated, unconscious or asleep.
There are 3 pillars often included in the description of sexual consent, or "the way we let others know what we're up for, be it a good-night kiss or the moments leading up to sex."
- Knowing exactly what and how much I'm agreeing to
- Expressing my intent to participate
- Deciding freely and voluntarily to participate
To obtain affirmative consent, rather than waiting to say or for a partner to say "no," one gives and seeks an explicit "yes." This can come in the form of a smile, a nod or a verbal yes, as long as it's unambiguous, enthusiastic and ongoing. "There's varying language, but the language gets to the core of people having to communicate their affirmation to participate in sexual behavior," said Denice Labertew of the California Coalition Against Sexual Assault. "It requires a fundamental shift in how we think about sexual assault. It's requiring us to say women and men should be mutually agreeing and actively participating in sexual behavior."