Persecution is the systematic mistreatment of an individual or group by another individual or group based on their membership in a religious, ethnic, social, or racial group. It is a crime that is defined as severe discrimination that results in the denial or infringement of fundamental rights. Fundamental rights referred to in the definition of persecution are generally understood to be those found in the Universal Declaration of Human Rights and the International Covenant on Civil and Political Rights, including the rights to life, liberty, security of person, equality and non-discrimination, freedom of expression and assembly and religion, and to be free from arbitrary arrest, detention, and cruel, inhuman and degrading treatment.

Persecution can take many forms, including mistreatment, ridicule, and discrimination based on religious beliefs or lack of religious beliefs. It can also involve the denial of basic human rights, such as the right to life, liberty, and security of person. When persecution is committed on a widespread or systematic basis, it is considered a crime against humanity.

Examples of persecution include the persecution of LGBTQ+ people, refugees, and migrants. Religious persecution is also common, with Christians, Hindus, and Muslims being among the groups that have historically been persecuted for their faith.