Georgetown Law
Technology Review

Saying “Hey Google,” “Hey Siri,” or “Alexa,” wakes voice command technology for use and allows voice assistants to help users complete everyday tasks. The convenience associated with voice assistants has caused their popularity to grow significantly over the past few years. However, substantial privacy concerns are also on the rise. First, users are not comfortable using voice assistants in public because users’ requests can be overheard. Second, the Fourth Amendment may not protect information disseminated to third-parties or conversations voice assistants overhear when they listen for their “wake” words.

To resolve the first concern, Microsoft developed and patented silent voice command technology that allows users to whisper requests to voice assistants in phones, watches, and other smart devices while users are in public. Microsoft developed the technology by conducting a study to determine how users whisper. The company found that users whisper by exhaling air. Yet, Microsoft’s patent states that silent voice command technology will require users to inhale air when making requests. Whispering while inhaling air is quite challenging, but the design significantly decreases users’ chances of being overheard in public because users’ voices are not projected outwards. Microsoft’s silent voice command technology can alleviate users’ privacy concerns and grow the voice command technology market by allowing users to feel comfortable making requests to voice assistants in public.

A drawback to the current patent is that to use silent voice command technology, plate or stick-shaped devices need to be within two millimeters of users’ mouths and touch their upper lips. Users need to create narrow air gaps and whisper into the devices to make requests. If the devices are used correctly, they can measure airflow with an accuracy of 98.8% to ensure users’ whispers are heard correctly. The goal is to make users feel comfortable using silent voice command technology because users’ privacy concerns will decrease, as the devices can prevent users from being overheard in public. Although, silent voice command technology may be uncomfortable to use because of its proximity to users’ mouths, implementing Microsoft’s silent voice command technology will encourage users to use voice assistants in public by protecting users’ privacy.

The second concern involving voice command technology is whether the Fourth Amendment’s reasonable expectation of privacy extends to voice assistants. Under the third-party doctrine, users lose Fourth Amendment privacy protections when information is voluntarily shared with third-parties. However, there remains an open question after the Supreme Court’s decision in Carpenter v. United States about whether the Fourth Amendment only protects third-party information pertaining to mobile location data or extends more broadly to additional third-party information. In Amazon Echo’s terms of service, Amazon states when users engage with third-parties, Amazon can share users’ information. Engaging with third-parties includes asking the temperature outside or playing music from streaming services. Due to the uncertainty of the third-party doctrine, law enforcement officers can obtain information third-parties receive without legal demands. Until Congress or the Supreme Court determine whether the Fourth Amendment protects information disseminated to third-parties by voice assistants, users’ privacy rights are uncertain and the use of voice assistants may decrease.

Another growing concern is whether the Fourth Amendment protects conversations voice assistants overhear when voice assistants listen for their “wake” words. Currently, law enforcement officers are trying to obtain conversations voice assistants overhear without legal demands. For example, a New Hampshire judge attempted to compel Amazon to share recordings from an Amazon Echo device that may have overheard a double murder. Amazon responded by stating it “will not release customer data without a valid and binding legal demand properly served on [them].” Amazon’s statement demonstrates that voice command technology companies are willing to protect private conversations overheard by voice assistants. However, until Congress or the Supreme Court determine whether Fourth Amendment protections are available to voice command technology users when voice assistants overhear conversations, companies bear the responsibility of protecting users’ privacy or users may cease to use voice assistants. In conclusion, voice command technology companies are attempting to carve out some protections for users’ privacy, although they are not completely secure.