In 1962, "Engel v. Vitale" held that the Establishment Clause prohibits mandatory prayer in public school. The ruling sparked a strong backlash from many political and religious leaders, some of whom called for the impeachment of Warren. Warren became a favored target of right-wing groups, such as the John Birch Society, as well as the 1964 Republican presidential nominee, Barry Goldwater. "Engel", the criminal procedure cases, and the persistent criticism of conservative politicians like Goldwater and Nixon contributed to a decline in the Court's popularity in the mid- and the late 1960s. "Griswold v. Connecticut" had the Court strike down a state law designed to restrict access to contraception, and it established a constitutional right to privacy. "Griswold" would provide an important precedent for the later case of "Roe v. Wade", which disallowed many laws designed to restrict access to abortion.