Sexual consent is an agreement to participate in a sexual activity (whether it involves physical contact or not). To be considered valid, consent must be free, informed and enthusiastic.
For sexual consent to be free, thus valid, people must feel like they have the choice to disagree. Therefore, if violence (ex. physical force, threat, etc.) is used and leads to a person saying “yes” to sex, this agreement is of no value because the person was forced to agree.
For sexual consent to be informed, thus valid, people must possess enough information to agree. Similarly, for sexual consent to be informed, people must also be in capacity to agree. For instance, when people have consumed (alcohol and/or drugs), their judgment can be impaired. It is therefore considered that they are incapable of providing informed consent. Even if people say “yes” to engage in a sexual activity, this agreement is of no value because they were under the influence of a substance. The same logic applies to people who are asleep or unconscious.
People must use their judgment as well as their empathy to recognize an enthusiastic, thus valid, sexual consent. Consent can be verbalized or not, using words and/or behaviours. Although all words and behaviours related to sexual consent must be coherent.