Paul Blanshard author of the much discussed book, "American Freedom and Catholic Power" will debate on the topic, "Catholic Church and Politics," in the Law School Forum at 8 p.m. tonight.

The Forum, which will be held in the Cambridge High and Latin School Auditorium, has been completely sold out for several days.

Upholding the position of the Roman Catholic Church will be Father George H. Dunne, S.J., author of "Religion and American Democracy" and pastor of St. Francis Xavier Church in Phoenix, Arizona. Father Dunne's book was written as a reply to "American Freedom and Catholic Power."

The appearance of Blanshard at the Forum was contested earlier this week by two alumni of the Law School. One of them, Richard W. Condon, a New York attorney, sent a letter to Dean Griswold in which he referred to Blanshard as a speaker "whose hallmark is the arousing of prejudice against a religious group."

Many Law School students, both Catholic and non-Catholic, have strongly supported the debate. Anthony P. Nugent, Jr. 3L, president of the Law Forum, in an answer to Condon stated that the Forum was bringing a competent opponent to Blanshard, and was interested only in exposing Blanshard's opinions so that the public could draw its own conclusions.

The Cambridge School Committee, which refused to allow Harold J. Laski to speak in the Cambridge High Auditorium last spring, has allowed Blanshard to speak, "because the presence of Father Dunne insures a fair debate."

Although the Forum is sold out, it will be possible to hear parts of the debate over the radio. WHDH is broadcasting the round table discussion and question period following the speeches. The broadcast will begin at 9:35 and will last approximately 40 minutes.

Blanshard's book, now in its ninth printing, discusses the "danger to American democracy from the medievalist of the Roman Catholic hierarchy." Parts of the book first appeared in "The Nation" a year ago last fall.