Religious discrimination is treating a person or group differently because of the particular beliefs which they hold about a religion. This includes instances when adherents of different religions, denominations or non-religions are treated unequally due to their particular beliefs, either before the law or in institutional settings, such as employment or housing.

Religious discrimination is related to religious persecution, the most extreme forms of which would include instances in which people have been executed for beliefs perceived to be heretic. Laws which only carry light punishments are described as mild forms of religious persecution or as religious discrimination.
Even in societies where freedom of religion is a constitutional right, adherents of religious minorities sometimes voice concerns about religious discrimination against them. Insofar as legal policies are concerned, cases that are perceived as religious discrimination might be the result of an interference of the religious sphere with other spheres of the public that are regulated by law (and not aimed specifically against a religious minority).
Religious discrimination in the United States

In a 1979 consultation on the issue, the United States Commission on Civil Rights defined religious discrimination in relation to the civil rights guaranteed by the Fourteenth Amendment to the United States Constitution. Whereas religious civil liberties, such as the right to hold or not to hold a religious belief, are essential for Freedom of Religion (in the United States secured by the First Amendment), religious discrimination occurs when someone is denied „the equal protection of the laws, equality of status under the law, equal treatment in the administration of justice, and equality of opportunity and access to employment, education, housing, public services and facilities, and public accommodation because of their exercise of their right to religious freedom“.
However, cases of religious discrimination might also be the result of an interference of the religious sphere with other spheres of the public that are regulated by law. Although e.g. in the United States the Free Exercise Clause of the First Amendment states that „Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof“, in Reynolds v. United States the U.S. supreme court decided that religious duty was not a suitable defense to a criminal indictment. In this specific case a law against bigamy was not considered to be discriminating against Mormons who stopped practicing Polygamy in 1890.
Religious discrimination in Germany

Scientologists in Germany face specific political and economic restrictions. They are barred from membership in some major political parties, and businesses and other employers use so-called „sect filters“ to expose a prospective business partner’s or employee’s association with the organization. German federal and state interior ministers started a process aimed at banning Scientology in late 2007, but abandoned the initiative a year later, finding insufficient legal grounds. Despite this, polls suggest that most Germans favor banning Scientology altogether. The U.S. government has repeatedly raised concerns over discriminatory practices directed at individual Scientologists.
Religious discrimination in Iraq

Assyrian Christians have suffered from discrimination since Saddam Hussein’s Arabization policies in the 1980s, with the latest instance of discrimination being the ISIS invasion of the Nineveh plains and Mosul, where tens of thousands have been forced to flee, and multiple Christian sites have been destroyed. The number of Christians in Iraq overall since the 2003 invasion has dropped by around 60%, from 800,000 to 300,000, and in 1987, that number was around 1.4 million. The 2014 invasion by ISIS has likely degraded that number further.
Sunni Muslims have also fallen victim to persecution from the majority Shia population of Iraq, which may have led to the ISIS invasion.