Contrary to some sources, he did not serve as a peritus or expert at the Second Vatican Council (1962-1965); that distinction belonged to Charles Arthur Curran, a member of the psychology department at Loyola University Chicago.

After a faculty-led strike that included students, the university reversed its position on Curran two weeks later and the trustees not only reappointed him, but also promoted him to associate professor with tenure.

[2][3] Curran later returned to prominence in 1968, becoming part of a group of 87 theologians who authored a response to Humanae vitae, Pope Paul VI's encyclical affirming the traditional ban on artificial contraception.

[7] Although a tenured professor, "clashes with Church authorities finally culminated in a decision by the Sacred Congregation for the Doctrine of the Faith, headed by then-Cardinal Joseph Ratzinger [later Pope Benedict XVI]".

[8] The areas of dispute included publishing articles that debated theological and ethical views regarding divorce, "artificial" contraception, masturbation, pre-marital intercourse and homosexual acts.

Despite strong support from ranking faculty committees, the institution’s president, James Martin, for reasons he would not disclose, refused to include tenure in Curran’s appointment.