Protesting snowpeople — complete with picket signs — joined a national avalanche of protest against a federal court that issued subpoenas for four antiwar activists in Des Moines.

It worked.

The federal government heard the protests, which had built since Friday, and acted Tuesday. The four activists no longer have to appear before a grand jury, and Drake University is no longer being asked to release its records related to a forum held on its Des Moines campus in November.

The snowpeople, built near Parks Library by members of the ISU chapter of the American Civil Liberties Union, were representations of the four Iowa antiwar activists, who were issued the subpoenas on the grounds of trespassing.

“This violation of liberty goes way beyond anything that has happened recently,” said Carolyn Heising, professor of industrial and manufacturing systems engineering. “You’d have to go back to the times of J. Edgar Hoover to find something like this.”

According to the Associated Press, antiwar activists gathered at Drake University Nov. 15 for a typical peace forum: a discussion of the philosophies of Mahatma Gandhi and Martin Luther King Jr. and how to translate their frustrations of the war in Iraq into demonstrations.

The day after the forum, some group members traveled to Camp Dodge, the Johnston headquarters of the Iowa National Guard. There they staged an antiwar demonstration, and a dozen people were arrested for trespassing.

Last week, subpoenas arrived ordering Drake University to give information about the forum and its leadership. Four protesters received subpoenas to appear before a federal grand jury. Among them was Brian Terrell, executive director of the Catholic Peace Ministry.

Protesters at Iowa State said they feared the subpoenas were intended to squash protesting rights through the powers of the Patriot Act, said Cara Harris, president of the ACLU at Iowa State.

“Under the Patriot Act, these protesters could be defined as terrorists because they were trying to coerce the government,” Harris said. “The government has sacrificed our civil liberties to create a false sense of security.”

Federal prosecutors said subpoenas were issued for events related to trespassing, not protesting, in order to escape criticisms that the government abused its powers granted by the Patriot Act.

“The investigation strictly concerns alleged unlawful entry onto military property … within the fenced security perimeter,” U.S. Attorney Stephen O’Meara said in a statement. “The U.S. Attorney’s office doesn’t prosecute persons peacefully and lawfully engaged in rallies which are conducted under the protection of the First Amendment.”

The case drew attention from national media such as the New York Times and the Chicago Tribune.

The National Lawyers Guild, which has more than 6,000 members and 100 law chapters, also threw its support behind Drake and the activists.

The Guild filed a motion Monday seeking to stamp out the federal subpoenas.

Before the investigation was called off Tuesday, government officials began to show signs of backing away from the investigation. Before dropping the subpoenas, prosecutors delayed grand jury appearances until March.

While political activists breathed a sigh of relief once the charges were dropped, they were still shaken by the events that transpired.

“I don’t think Catholic peace activists are domestic terrorists,” Heising said. “Where will they draw the line?”

— The Associated Press contributed to this article.