The police in Bentonville, Arkansas have asked Amazon to give them access to any voice recordings that its Echo digital assistant may have made at the time that an alleged murder was committed, reports The Information. According to court documents James Andrew Bates is charged with killing Victor Collins on November 22, 2015 after Collins was found dead in Bates' hot tub.

Echo operates by always listening for "hot words" that signal it to send a request to the cloud services offered by Amazon and various third parties. For example, owners might ask Echo through Amazon's voice recognition program Alexa for a weather report or to play Mozart. The device retains fewer than 60 seconds of recorded sound in its storage buffer.

Amazon records all requests with the idea that Alexa will learn better over time how to respond to specfic customers' queries and orders. However, Echo does not record every word that people say in their homes. In other words, always listening is not the same as always recording.