TACOMA — A federal judge said he has “ethical and legal” concerns over the Department of Justice’s decision to take control of a child-pornography bulletin board and allow the distribution of as many as 1 million illegal images while agents hacked the computers of the site’s visitors.

U.S. District Judge Robert Bryan also confronted Department of Justice (DOJ) prosecutors over their continued insistence that the government’s actions in taking over and secretly operating the “dark web” bulletin board for two weeks in 2015 were somehow innocent.

Bryan presided over a two-day hearing in Tacoma on motions to suppress evidence gathered in that investigation against three Washington men, David Tippens, Gerald Lesan and Bruce Lorente, who are accused of viewing and receiving child pornography. He took the matter under advisement.

During the hearing, the deputy director of the DOJ’s New York-based Child Exploitation and Obscenity Section, Keith Becker, argued that allowing the site to remain active was an “investigative necessity.”

“The government itself did not post or create child pornography,” Becker told the court.

Bryan interrupted him.

“Y’all were doing just exactly what the people who were in charge of that website were doing before you arrested them,” he said.

At another point, as Becker was describing the “huge social costs” that would result if the court were to exclude evidence in these cases, Bryan stopped him again.

“You talk about social costs? There are huge social costs in constitutional violations, too,” the judge said.

The prosecutions in Washington of Tippens, Lesan and Lorente — all swept up in an FB sting called “Operation Pacifier” — are at the forefront of a growing number of challenges to the 214 cases around the country that so far have resulted from the investigation. The courts have been divided in their rulings on whether the FBI went too far, and prosecutors and defense lawyers say the case is almost certainly headed to the U.S. Supreme Court.

The cases are spurring national debate over internet privacy and the reach of law enforcement in the digital age.

Bryan has already excluded evidence in an earlier Washington case, involving a Vancouver School District employee named Jay Michaud, because the FBI refused to turn over to defense attorneys the details of a so-called “Network Investigative Tool” (NIT) it used to hack into the computers of visitors to a dark-web child-porn bulletin board called “The Playpen.”

The prosecutions of Tippens, Lesan and Lorente have now reached the same stage in their proceedings, and their attorneys have attacked the government’s cases on several fronts:

• They accused the government of “outrageous conduct” by allowing agents to potentially commit crimes more serious than those they were pursuing by distributing pornography.

• They also allege the DOJ intentionally violated the federal Rules of Criminal Procedure — and the will of Congress — by circumventing a requirement that warrants be issued by a magistrate in the same district as the crime allegedly occurred. Instead, they say agents had a Virginia magistrate judge issue a single search warrant that was used to hack into as many as 100,000 computers in 120 countries

• They say evidence should be excluded or suppressed because the DOJ has violated the rules of discovery in a criminal case by continuing to refuse to turn over the details of the NIT.

Assistant U.S. Attorney Matthew Hampton said agents were faced with “tough choices” throughout the investigation and suggested that the federal rules have not kept up with technology.

“These are bad people who hurt children,” he said. “The government did what was necessary.”

“I don’t know who was making those decisions,” Judge Bryan said. “But I am concerned both ethically and legally.”