The popular rap on Google Glass facial-recognition technology is that it’s a tool for creeps and stalkers. But Google’s decision to ban both facial-recognition and voiceprint technology from its high-tech eyewear also puts the brakes on promising services, like those that could help medical staff rapidly retrieve patient records.

At a recent conference, developer Lance Nanek showed off a medical facial-recognition Glass app he built that could—for a set of patient faces entered into the system—allow Glass-wearing clinicians to verify someone’s identity and instantly bring up records on allergies or existing prescriptions, without ever turning to a cumbersome PC or mobile handset.

All that’s on hold now. Facing heat from Congress, Google late last week announced on its Google+ page that it was banning facial-recognition apps. The ban went further than that; updates to the actual developer policy expanded the ban to voiceprints, saying that any applications that use the camera or microphone to “immediately” identify anyone other than the user “will not be approved at this time.”

And under its developer overview, Google ultimately controls what the display output of any application will be on Glass. This implies that Google could even block people from sending out a face photo, getting it recognized, and then seeing the results on Glass—even if a facial-recognition app isn’t directly written for Glass. The company left open the possibility that future privacy-protection technologies might prompt a policy change.

All of this was a bummer to Nanek. “Whenever I go to my doctor, they have to sit down in front of a computer, type in a bunch of stuff, bring up records, and scroll around,” he says. “The MDs who saw this were like, ‘Man, it would really help if I saw test results immediately, and saw the results when I looked at the patient. I could see if medications were conflicting.’ Anything that saves a little bit of time is worth a lot.”

It wouldn’t be good enough to use facial recognition on another type of device, Nanek says, because the clinician would still have to take multiple extra steps—snap a photograph, open an app to compare the photo against a database, and refer to the screen to see the resulting data.

Google’s decision to put the brakes on facial and voice recognition basically cuts off a major motivation to develop apps for the technology, adds Stephen Balaban, a developer and cofounder of Lambda Labs, a startup selling a programming interface for the glasses hardware.

“My opinion is that face-recognition technology is a core functionality, a core feature of the wearable computer,” Balaban says. “Whatever wearable computing platform becomes successful—whether it is Google Glass or something else—will have this functionality. In the long run, this decision is going to hurt the Glass ecosystem. They are creating a walled garden that won’t put people in a creative mind-set exploring this space. They’ll be thinking, ‘Will Google approve my application?’ ”

Instant facial recognition could also help police identify people on a most-wanted list (updatable in real time), and it would be useful to people with neurological disorders that make it hard to recognize faces. “I’m pretty disappointed,” Nanek says.

Google Glass is prototype eyewear that can display information to the wearer, snap still photos and video, and both download and upload information to a Bluetooth-connected smartphone. Google has made the technology available to developers and says it wants to start selling the device within a year. But members of Congress wrote two weeks ago to CEO Larry Page to ask whether the company would prevent “unintentional” collection of data and whether it would allow facial recognition—demanding a response by June 14. The ban came after the congressional letter.

What else would people do with Glass? Google has been heavily promoting the sharing of point-of-view photos on its social network, Google+, but that isn’t necessarily going to be more interesting than just taking photos the usual way (see “Google Glass Testers Spam Google Social Network”).

“Right now, they aren’t saying this is a great new platform,” Balaban said. “They are saying this is a way to share photos with people on Google+. So they might be blindsided by another company whose focus is on a wearable computing platform, not a photo-sharing app for Google+.”

A Google spokesman, Chris Dale, declined to comment.