Albert Sprague Coolidge '15, lecturer in Chemistry, led the opposition yesterday against a proposed amendment to the state constitution that would bar "subversive" persons from voting or holding public office.

Coolidge appeared with witnesses from the Massachusetts Civil Liberties Union, representatives of political organizations, and private citizens, testifying before the Constitutional Law Committee of the General Court at the State House.

When a committee member broke into the testimony to ask if Professor Dirk J. Struik of MIT had violated the teachers' oath law by alleged subversive activities, Coolidge replied that he was "not satisfied" that Struik has advocated violent overthrow of the national government. Struik has every right to free speech, Coolidge said, adding that "it's a healthy thing to have a few cranks in a university."

Kirtley F. Mather, professor of Geology, was unable to testify because of his morning lecture schedule. Mather was named an active supporter of Communist fronts last week by Joseph B. Matthews, ex-Dies Committee investigator, who spoke in favor of the proposed amendment.