If you sleep on your Apple Watch the wrong way, you might get a wake-up call from the police. That’s what happened to Jason Rowley, who tweeted about the incident earlier this week. Using his watch as a sleep tracker, he ended up holding down the crown button to trigger an emergency call to the police, who showed up in his bedroom at 1AM. Rowley told us the police were friendly and helpful, and accustomed to WatchOS misdials like this one.

Public service announcement: If you sleep with an Apple Watch on, consider turning off the Emergency SOS feature, or you too may wake up to 3 cops in your bedroom at 1 AM. — Jason D. Rowley (@Jason_Rowley) March 16, 2018

If you scan through Twitter, you’ll find a surprising number of stories like Rowley’s. It’s a problem for iPhones too, since the same alert can be triggered through the side button. (One Verge staffer triggered an alert after mistaking the power button for the volume controls.) In each case, you’ll get a blaring countdown and have three to five seconds to turn it off before your device calls 911 and texts any emergency contacts you’ve set up.

fuck i accidentally hit my lock button multiple times out of a nervous twitch and it activated my emergency SOS alarm and made everyone in class freak out lmfao i wanna leave this class forever — kwami (@fuckkristinb) March 6, 2018

The feature is called Emergency SOS, rolled out as part of WatchOS 4 and iOS 11. (There’s a similar feature on Android too.) The premise is simple enough: if you’re in danger or otherwise in need of help, holding down the right buttons will let you summon help without drawing attention to yourself. It’s a potentially life-saving feature, but of course butt dials are going to be more common than actual emergencies.

Apple Watch really needs a “I’m changing bands please don’t trigger emergency SOS or password wipe” mode — Colin Weir (@radiocolin) March 15, 2018

The exact sequence of buttons varies from device to device. A Watch will slip into an alert just from holding down the crown button long enough, which seems to be a particular danger if you wear it to sleep. If you’re running the latest iOS on an iPhone 7 or older, you trigger an SOS by tapping the side button five times (apparently a common practice for fidgeters), and more recent iPhones will start the countdown just from holding the button.

Of course, you can fix some of this by turning off Autocall in Settings > Emergency SOS, which will add an extra slider step. But it’s easy to see why you might not want to. Maybe a few accidental 911 calls isn’t so bad compared to the risk of an actual emergency? Still, it seems like it would be useful for clumsy users to have a way to turn SOS all the way off.