Attorneys for the government and Samuel L. Popkin, assistant professor of Government argued Popkin's appeal yesterday before three justices of the First Circuit Court of Appeals.

Popkin is appealing a March 29 decision in Federal District Court which found him in civil contempt for refusing to answer certain questions before a Boston grand jury investigating the distribution of the Pentagon Papers to the press.

A decision on the appeal is required by law by April 28.

Speculation exists among legal observers that previously denied motion by Popkin's attorneys that would have required the government to reveal the nature of any intercepted oral or wire communications may play an important part in the court's decision.

It is possible that the First Circuit Court of Appeals may try to decide Popkin's case on the narrowest possible terms without making a broad constitutional ruling.

The court said yesterday that although the possibilities of widespread occupational privilege which a pro-Popkin decision might being were disturbing. It found the government's argument for poser "equally disturbing if not more so."

The motion for disclosure of surveillance was included superficially in Popkin's brief; the court asked yesterday that Popkin's attorneys clarify that request. They are expected to file papers this morning.

William P. Homans Jr. '41, representing Popkin, argues his case for about 35 minutes yesterday before the justices. In addition to summarizing the points raised in his brief--which leaned on a parallel between the privilege of a scholar and that of a journalist under the Caldwell ruling-- Homans clarified several points raised by the court.

These included dates on publication of some Popkin articles and the limitations of Popkin's refusal to answer.

The government, represented by Assistant U.S. Attorney Warren P. Reese, argued that no scholarly privilege should exist. Asked by the court whether this might have a detrimental effect on further research--as affidavits for Popkin state--Reese replied that "although there may be a chilling effect, the interest of the public must be balance" Against the possible harm to the national security.