Hennepin County Sheriff Dave Hutchinson began encrypting all 911 calls and law enforcement radio traffic Wednesday, meaning the calls and conversations cannot be tracked by the public and news media.

The radio silence reverses the decadeslong practice of allowing the public to listen and react to law enforcement calls and activity in real time. The encryption goes beyond the Sheriff’s Office, affecting 25 law enforcement departments that receive 911 dispatch service through the county. The change does not affect fire departments or emergency medical services.

Hennepin County is the first known agency in the state to encrypt the calls.

The decision was made based on the recommendation of an advisory committee. It’s a reversal in philosophy for Hutchinson, who in 2018 said he would not encrypt the radio and traffic calls. He took office in January.

“He has come around to accepting this is the right move for our agency,” spokesman Jeremy Zoss said Wednesday, calling the decision a matter of “best practices” in law enforcement.

While it’s not uniform, a few cities across the country have moved to encryption. Denver did so last summer.

For decades, police scanners have been a major tool for journalists and other interested citizens to track what was happening on the streets. Scanners aren’t as singular as they once were because of the rise in social media, but they can still provide real-time alerts. The decision by Hennepin County was not met with enthusiasm by government access advocates.

Don Gemberling, spokesman for the Minnesota Coalition on Government Information (MNCOGI), said it’s ironic that law enforcement wasn’t concerned about who listened to scanner traffic until the technology became available. “And,” he added, “we have a new sheriff.”

Among the affected departments are Golden Valley, Brooklyn Center, Brooklyn Park, Robbinsdale, Mound, Minnetrista, Orono, Ply­mouth, Maple Grove, Minnetonka, Wayzata and New Hope. Through the first week of September, the county 911 dispatch has received 482,253 phone calls this year for both emergencies and nonemergencies, Zoss said.

The decision wasn’t in response to any specific incident, but the Sheriff’s Office decided to switch to encryption for two reasons: privacy and safety, Zoss said.

Zoss said increasingly people have less control over their personal information, and this is another way to rein in the release. “If someone is having a domestic in their home, they probably don’t want that going out” on the radio, he said.

The other concern is that criminals can track law enforcement movements through scanner traffic. “We don’t want to be sharing tactical information,” he said.

Gemberling questioned whether that was happening.

“Where is the evidence? Where are the gross invasions of privacy?” he asked. “Where are the tactical situations that got screwed up because somebody was using a scanner?”

Zoss said he wasn’t able to provide “real world examples” from Minnesota of problems traced to radio traffic and 911 calls, but that in 2015, suspects in a Planned Parenthood clinic shooting in Colorado Springs were able to monitor scanner traffic. He said the county is considering special access for news organizations. Zoss said he thinks the county will allow news outlets to rent devices that can decode the scanner traffic.

To Gemberling, the encryption is part of a bigger concern about government using technology to gather and conceal information.

“As we use more and more technology to do law enforcement, we know less and less about what law enforcement is doing,” he said. For example, he cited the state law governing when footage from police body cameras must be released as one of the most restrictive in the nation.

He expects other law enforcement agencies to follow Hennepin County’s lead.

But Ramsey County, which runs the largest Emergency Communications Center in the state for numerous east metro cities and St. Paul, has no plans to make the move. County spokesman John Siqveland said that for more than a decade some specialized units, such as SWAT and special investigations, have used encryption. “We have had no conversations with any of our agencies about broad adoption of encrypted radio,” he said.

In Minneapolis, police have used encrypted channels for sensitive investigations, but not for 911 calls and radio traffic. “We do not have any plans to go to encryption,” spokesman John Elder said.

Last month, Hutchinson’s office revamped the online county jail roster, which reduced the information publicly available about jail inmates. Reversing long-standing practice, the website initially did not include the addresses and birthdates of those booked into the jail.

Hutchinson reversed parts of that decision when he learned that addresses of detainees are public under state law, Zoss said. Instead of birthdates, he now provides detainees’ ages. Birthdates could make inmates susceptible to identity theft, Zoss said.

Birthdates, however, are available in other government databases and can be critical to verifying identities.

Pat Doyle, a retired Star Tribune reporter who is also on the board of MNCOGI, called Hutchinson’s actions “goofy and unnecessary.”

“It just makes it that much harder for the average guy to get information,” Doyle said.

The final irony, Gemberling said, is “somewhere there’s a bunch of guys who are going to figure out how to defeat the encryption, and they won’t be the good guys.”

Rochelle Olson • 612-673-1747