Samuel L. Popkin, lecturer in Government, was freed from prison yesterday after the U.S. government disbanded the Boston grand jury investigating the Pentagon Papers case.

Popkin had served one week of a sentence imposed for his continual refusal to answer questions before the grand jury.

Reliable sources told The Crimson yesterday that Daniel Stemer '54 general counsel to the University played a "highly significant part in negotiations to release Popkin.

Stemer met last Friday with william Olson chief of the justice Department's Internal Security Division to discuss ways to arrange Popkin's release. Stemer yesterday declined comment on the meeting but a high level source reported that it was a full and fair hearing of the issues involved The source further reported that the meeting "did have a role in getting Popkin out".

No More Evidence

Olson could not be reached for comment yesterday Representatives of the U.S. Attorneys office said in court yesterday before District Judge Frank J. Murray that there would be no more evidence presented to the grand jury until the completion of the trial of Daniel Elisberg '62 in San Diego.

They said that Elisberg's trial would probably extend past the grand jury's January 12 expiration date and that for this reason the grand jury should disband. The grand jury entered no indictments during its 16-month existence.

Popkin said in a news conference yesterday that grand juries "have become. the government's feel for gathering intelligence," and warned that "today we may be faced with as great a threat from the use of grand juries as was ever posed by Joe McCarthy."

He added that he still does not know, and probably never will know, why he was called before the grand jury and what the government expected him to say. Their questions "do not reveal a clear pattern of what they were after," he said.

Popkin added that "there's an incredible bag of tricks that go along with grand juries in this country," and said that people should not worry so much about the privileges of scholars and journalists but instead should "clean up the grand jury."

Popkin praised his attorneys. William P. Homans '41, and Daniel Klubock, and many other people in and out of prison for giving him the strength to adhere to any principles.

"I am equally glad that this and other cases have alerted people to the threat posed by the use of grand juries to the First Amendment and the free inquiry I believe it protects," Popkin said.

Popkin warned that if scholars and journalists cannot talk confidentially with officials, "the First Amendment will protect nothing more than polemics and official handouts."

He added that he considered scholars information equally protected with journalists under the Constitution asking "What is the difference between writing for a newspaper or writing a book."

Popkin speculated that perhaps the grand jury was prepared to disband earlier but remained in session long enough to force him late prison.