For the police, unlocking your iPhone X could be the same as taking your mugshot, thanks to Face ID.

One of the marquee features of Apple's latest flagship phone, Face ID uses multiple scanners for facial recognition. That's great for preventing people from snooping, but as its Touch ID counterpart has shown, biometric technology doesn't hold up in court as well as an old-fashioned password.

In trials, judges have ruled that people need to give up their fingerprints to unlock their iPhones via Touch ID. Now Face ID will face the same legal vulnerability.

So it's important to note that as secure as Apple has made Face ID, you'll want to consider a simple password to defend yourself against both hackers and the authorities. That's because unlike passwords, biometrics like facial and fingerprint recognition aren't protected by the US Constitution.

Now playing: Watch this: Apple explains Face ID on iPhone X

The iPhone X won't be available until November, but legal and security experts can already envision scenarios in which police will force people to use their face to unlock the phones.

"Biometrics are going to give you less protection in a law enforcement context than you would have if you were using a password," said Josh King, the chief legal officer at online legal services marketplace Avvo.

Courting Face ID

It's not quite as simple as an officer holding a phone to a face to unlock the device. It's illegal for police to search your phone without a warrant, the Supreme Court ruled in 2014. Also, as Apple pointed out at the iPhone X launch, Face ID needs your attention to do the unlocking. Hypothetically, you could keep your eyes closed to prevent Face ID from working.

Unless the officers have a warrant.

Courts have ruled that police can compel people to unlock their devices through Touch ID with a warrant. It happened in 2014 in a Virginia circuit court ruling, and again in 2016 when a Los Angeles judge granted a warrant to force a suspect to unlock her iPhone using a fingerprint.

In his decision, the Virginia judge compared the matter to giving police your thumbprints or a DNA sample. Considering that people regularly pose for police mugshots, Face ID could fall under the same logic.

"The same rules that applied to fingerprints will likely apply to Face ID," said Brett Kaufman, the staff attorney for the American Civil Liberties Union. "If you use a biometric, you've basically sold away some strong arguments that you would have with the Fifth Amendment."

Enlarge Image Apple/Screenshot by CNET

The Fifth Amendment protects people from self-incrimination, like giving your password away. But it's different for biometrics. Judges likely won't see your face and your fingerprints as something kept private -- you already provide it during processing.

And unlike with your password, refusing to give your fingerprint or hold still for a photo would be considered obstruction of justice, Kaufman said.

"If you're under arrest, and the police are asking you to stare at the camera to take a picture, just because you have a Fifth Amendment right doesn't mean you can act in ways that obstruct your processing," he said.

Setting precedent

There are also concerns that law enforcement officials will circumvent warrants to unlock devices with Face ID. The ACLU is suing the Department of Homeland Security for searching travelers' phones and laptops without warrants at border stops.

And police don't need warrants if they have consent. Dasha Cherepennikova, the chief strategy officer of One World Identity, a privacy research company, believes most people give consent to phone searches to avoid further trouble.

"I think a lot of people would feel pressured to do it, regardless of the legality," Cherepennikova said.

The first court case deciding whether Face ID is protected will have lasting effects on how Apple can secure your privacy, King said.

"It'll be pretty important -- it's going to be the single data point for Face ID," King said. "All we've had so far are a couple of trial court-level cases on biometrics. This stuff is very new. It could certainly change."

Apple's workarounds

Apple values security and privacy, and even went to bat against the FBI in 2016 after the agency demanded that it unlock an iPhone 5C belonging to one of the San Bernardino terrorists. The FBI backed down before the sides could face off in court, but the clash showed the world how far Apple would go to protect people's privacy. With the newly arrived iOS 11, Apple has provided some ways to stop Face ID from working against you.

"Our teams have been developing the technologies behind Face ID for several years, and our users' privacy has been a priority since the very beginning," Apple said.

The latest operating system for the iPhone introduced a shortcut to disable your device's Touch ID and Face ID.

"If you grip the buttons on both sides of the phone when you hand it over, it will temporarily disable Face ID," Craig Federighi, Apple's senior vice president of software engineering, said in an email to a developer.

The iPhone X also automatically disables Face ID if the device hasn't been unlocked for more than 48 hours or if it gets a remote lock command, the company said.

That means that if it takes more than two days to get a warrant to unlock your phone through Face ID, you could be protected. But Touch ID had a similar protection, and it did not stop the courts from forcing people to unlock their devices through fingerprints.

For now, the password remains your safest bet.

"There's so much unsettled law here that I think the safest approach is not to use these kinds of features," Kaufman said.

The Smartest Stuff: Innovators are thinking up new ways to make you, and the things around you, smarter.

Logging Out: Welcome to the crossroads of online life and the afterlife.