Excerpt from this article:
Arkansas police recently demanded that Amazon turn over information collected from a murder suspect’s Echo. Amazon’s attorneys contend that the First Amendment’s free speech protection applies to information gathered and sent by the device; as a result, Amazon argues, the police should jump through several legal hoops before the company is required to release your data.
… Let’s look at a few scenarios. These are more or less specific to Amazon’s technology and policies, but variants could apply to Google Home or other digital assistants. This brings up a more basic question: Do you have to give informed consent to be recorded each time you enter my Alexa-outfitted home? Do I have to actively request your permission? And who, at Amazon or beyond, gets to see what tendencies are revealed by your Alexa commands? Amazon claims you can permanently delete the voice recordings, though wiping them degrades performance. Even if you’re smart enough to clear your browser history, are you smart enough to clear this, too? And what about the transcripts?
Another question: How do you know when your digital assistant is recording what you say? Amazon provides several ways to activate the recording beyond the “wake” word. A light on the Echo turns blue to indicate audio is streaming to the cloud. After the request is processed, the audio feed is supposed to close. You can also set the device to play a sound when it stops streaming your audio, but what happens if the device is hacked or modified to keep recording?