Ireland's data privacy regulator has asked Facebook to demonstrate that an LED indicator light on the social media giant's newly launched smart glasses is "an effective means" to let people know they are being filmed or photographed.
Facebook's Ray-Ban Stories allow wearers to listen to music, take calls or capture photos and short videos and share them across Facebook's services using a companion app.
The LED light on the glasses is supposed to show when the camera is operational, but early users identified a flaw in the system - it can simply be taped over.
Buzzfeed News technology reporter Katie Notopoulos was one of those who did so, revealing that taping over the LED doesn't stop the camera from working.
"Facebook is making camera glasses. They have an LED warning light so that bystanders know you are taking a video," she tweeted.
"I taped it over. A FB exec told me this is a violation of the terms of service of the glasses (oops)."
Wall Street Journal senior personal technology columnist Joanna Stern was another who was able to breach people's privacy.
In her review she wrote how she "spent the week being a total creeper and recording lots of people who didn't know until I told them".
She concluded, in a tweet: "I also appreciate that Facebook consulted with privacy experts on this but seems like they didn't go as far as many would have liked."
Ireland's Data Privacy Commissioner (DPC) is the lead regulator of Facebook under the European Union's strict data privacy laws as the firm's European headquarters are based in Dublin.
"While it is accepted that many devices including smartphones can record third party individuals, it is generally the case that the camera or the phone is visible as the device by which recording is happening, thereby putting those captured in the recordings on notice," the Irish regulator said in a statement.
The Irish regulator said it shares the concerns of the Italian Data Protection Regulator, the Garante, which asked Facebook for clarifications on September 10 to assess the smart glasses for compliance with privacy laws.
"With the glasses, there is a very small indicator light that comes on when recording is occurring," the DPC said.
"It has not been demonstrated to the DPC and Garante that comprehensive testing in the field was done by Facebook or Ray-Ban to ensure the indicator LED light is an effective means of giving notice."
Facebook had published a guide outlining how to use the glasses responsibly, for example turning them off in private spaces like public bathrooms and not using them for illegal actions like harassment or capturing sensitive information such as PIN codes.
But the DPC wants Facebook to run an information campaign to alert the public as to how this new consumer product may give rise to less obvious recording of their images.