Discrimination against atheists includes the persecution and discrimination faced by atheists and those labelled as atheists in the past and in the current era. Differing definitions of atheism historically and culturally mean that those discriminated against might not be considered truly atheist by modern Western standards. In constitutional democracies, legal discrimination against atheists is uncommon, but some atheists and atheist groups, particularly those in the United States, have protested laws, regulations and institutions that they view as being discriminatory. In some Islamic countries, atheists face discrimination including lack of legal status or even a death sentence in the case of apostasy.

Ancient times

Historians including Lucien Febvre agree that atheism in its modern sense did not exist before the end of the seventeenth century. However, as governmental authority rested on the notion of divine right, it was threatened by those who denied the existence of the local god. Philosophers such as Plato argued that atheism was a danger to society and should be punished as a crime. Those labeled as atheist, which included early Christians and Muslims, were as a result targeted for legal persecution.

Early modern times

During the Middle Ages, the term "atheist" was used as an insult and applied to a broad range of people, including those who held opposing theological beliefs, as well as suicides, immoral or self-indulgent people, and even opponents of the belief in witchcraft. Atheistic beliefs continued to be seen as threatening to order and society by philosophers such as Thomas Aquinas. Lawyer and scholar Thomas More asserted that religious tolerance should be extended to all except those who did not believe in a deity or the immortality of the soul. Even John Locke, a founder of modern notions of religious liberty, argued that atheists (as well as Catholics and Muslims) should not be granted full citizenship rights.

During the Inquisition, several of those accused of atheism and/or blasphemy met gruesome fates. These included a priest Giulio Cesare Vanini who was strangled and burned in 1619 and a Polish nobleman Kazimierz Lyszczynski who was executed in Warsaw, as well as Etienne Dolet, a Frenchman executed in 1546. Though heralded as atheist martyrs during the nineteenth century, recent scholars hold that the beliefs espoused by Dolet and Vanini are not atheistic in modern terms.

During the nineteenth century, British atheists, though few in number, were subject to discriminatory practices. Those unwilling to swear Christian oaths during judicial proceedings were unable to give evidence in court to obtain justice until the discrimination was ended by Acts passed in 1869 and 1870. In addition, the poet Percy Bysshe Shelley was expelled from the University of Oxford and denied custody of his two children after publishing a pamphlet on "The Necessity of Atheism".  Avowed atheist Charles Bradlaugh was elected member of the British parliament in 1880. He was denied the right to affirm rather than swear his oath of office and was expelled from House, but was reelected several times. He was finally able to take his seat in 1886 when the Speaker of the House permitted the affirmation.

In Germany during the Nazi era, a 1933 decree stated that "No National Socialist may suffer detriment... on the ground that he does not make any religious profession at all".  However, the regime strongly opposed "godless communism", and most of Germany's atheist and largely left-wing freethought organizations were banned the same year; some right-wing groups were tolerated by the Nazis until the mid 1930s. In a speech made later in 1933, Hitler claimed to have "stamped [atheism] out".

Modern era

Western countries

Modern theories of constitutional democracy assume that citizens are intellectually and spiritually autonomous and that governments should leave matters of religious belief to individuals and not coerce religious beliefs using sanctions or benefits. The constitutions, human rights conventions and the religious liberty jurisprudence of most constitutional democracies provides legal protection of atheists and agnostics. In addition, freedom of expression provisions and legislation separating church from state also serve to protect the rights of atheists. As a result, open legal discrimination against atheists is not common in most Western countries.

Europe

In Europe, atheists are elected to office at high levels without controversy. Some atheist organizations in Europe have expressed concerns regarding issues of separation of church and state, such as administrative fees for leaving the Church charged in Germany, and sermons being organized by the Swedish parliament.

Canada

Canadian humanist groups have worked to end the recitation of prayers during government proceedings, viewing them as discriminatory.

United States

Some atheists assert that they are discriminated against in the United States and compare their situation to the discrimination faced by ethnic minorities, LGBT communities and women. "Americans still feel it's acceptable to discriminate against atheists in ways considered beyond the pale for other groups," asserted Fred Edwords of the American Humanist Association. Other atheists reject these comparisons, arguing that while atheists may face disapproval they have not faced significant oppression or discrimination.

In the United States, seven state constitutions officially include religious tests that would effectively prevent atheists from holding public office, and in some cases being a juror/witness, though these have not generally been enforced since the early nineteenth century. The US Constitution allows for an affirmation instead of an oath in order to accommodate atheists and others in court or seeking to hold public office. In 1961, the United States Supreme Court explicitly overturned the Maryland provision in the Torcaso v. Watkins decision, holding that laws requiring "a belief in the existence of God" in order to hold public office violated freedom of religion provided for by the First Amendment to the United States Constitution. This decision is generally understood to also apply to witness oaths.

Several American atheists have used court challenges to assert discrimination against atheists. Michael Newdow challenged inclusion of the phrase "under God" in the United States Pledge of Allegiance on behalf of his daughter, claiming that the phrase was discriminatory against non-theists. He won the case at an initial stage, but the Supreme Court dismissed his claim, ruling that Newdow did not have standing to bring his case, thus disposing of the case without ruling on the constitutionality of the pledge.

As the Boy Scouts of America does not allow atheists as members, atheist families and the ACLU from the 1990s onwards have launched a series of court cases arguing discrimination against atheists. In response to ACLU lawsuits, the Pentagon in 2004 ended sponsorship of Scouting units, and in 2005 BSA agreed to transfer all Scouting units out of government entities such as public schools.

Atheists note that few politicians have been willing to identify as non-theists, since until recently such revelations would have been "political suicide", and welcomed Representative Pete Stark's 2007 decision to come out as the first openly nontheistic member of Congress. Several polls have shown that about 50 percent of Americans would not vote for a well-qualified atheist for president. A 2006 study found that 40% of respondents characterized atheists as a group that did "not at all agree with my vision of American society", and that 48% would not want their child to marry an atheist. In both studies, percentages of disapproval of atheists were above those for Muslims, African-Americans and homosexuals.

Prominent atheists and atheist groups have asserted that discrimination against atheists is illustrated by a statement allegedly said by George H. W. Bush during a public press conference during his campaign for the presidency in 1987. When asked by atheistic journalist Robert Sherman about the equal citizenship and patriotism of American atheists, Sherman reports that Bush answered "No, I don't know that atheists should be considered as citizens, nor should they be considered patriots. This is one nation under God." The accuracy of the quote has been questioned, however, as Sherman did not tape the exchange and no other journalist reported on it.

Islamic countries

Atheists, or those accused of holding atheistic beliefs, may be subject to discrimination and persecution in some Islamic countries. According to popular interpretations of Islam, Muslims are not free to change religion or become an atheist: denying Islam and thus becoming an apostate is traditionally punished by death in men and by life imprisonment in women, though in only three Islamic countries is apostasy currently subject to capital punishment. Since an apostate can be considered a Muslim whose beliefs cast doubt on the Divine, and/or Koran, claims of atheism and apostasy have been made against Muslim scholars and political opponents throughout history.

In Iran, atheists do not have any recognized status, and must declare that they are Muslim, Christian, Jewish or Zoroastrian, in order to claim some legal rights, including applying for entrance to university, or becoming a lawyer. Similarly, Jordan requires atheists to associate themselves with a recognized religion for official identification purposes, and atheists in Indonesia experience official discrimination in the context of registration of births and marriages, and the issuance of identity cards. In Egypt, intellectuals suspected of holding atheistic beliefs have been prosecuted by judicial and religious authorities. Novelist Alaa Hamad was convicted of publishing a book that contained atheistic ideas and apostasy that were considered to threaten national unity and social peace. Compulsory religious instruction in Turkish schools is also considered discriminatory towards atheists.

 - Sources: Wikipedia