When police responded to a home in Bentonville, Ark., one Sunday morning in November 2015, they discovered Victor Collins' dead body in the backyard. Police records describe a grim scene: Collins' body was floating face up in a hot tub, his left eye and lips dark and swollen.
The resident who had called 911, James A. Bates, told police that he and a few work buddies, including Collins, had stayed up the night before watching football and drinking. Bates agreed to let two of them crash at his house, then went to bed, he told police. Shortly after he awoke, he said, he spotted Collins' lifeless body in the spa.
But upon further investigation, police began suspecting foul play. Broken knobs and bottles, as well as blood spots around the tub, suggested that there had been a struggle. A few days later, the Arkansas chief medical examiner ruled Collins' death a homicide, and police obtained a search warrant for Bates' home.
Inside, detectives discovered a bevy of "smart home" devices, including a Nest thermometer, a Honeywell alarm system, a wireless weather monitoring system and an Amazon Echo. Police seized the Echo and served a warrant to Amazon, saying in the affidavit there was "reason to believe that Amazon.com is in possession of records related to a homicide investigation being conducted by the Bentonville Police Department."
That warrant threw a wrinkle into what might have been a traditional murder investigation, as first reported by the Information, a news site that covers the technology industry.
Police have long seized computers, cellphones and other electronics to investigate crimes, but this case has raised fresh questions about privacy issues regarding devices such as the Amazon Echo and the Google Home, voice-activated personal command centers that are constantly "listening." Namely, is there a difference in the reasonable expectation of privacy one should have when dealing with a device that is "always on" in one's own home?
The Echo is equipped with seven microphones and responds to a "wake word," most commonly "Alexa." When it detects the wake word, it begins streaming audio to the cloud, including a fraction of a second of audio before the wake word, according to the Amazon website.
A recording and transcription of the audio is logged and stored in the Amazon Alexa app. For instance, if you asked your Echo, "Alexa, what is the weather right now?" you could later go back to the app to find out exactly what time that question was asked.
Police did not specify what data they expected to find on Bates' Echo — nor is it clear what the device could have captured that would have been relevant to the case. Only if someone happened to have triggered his device with its wake word would it have begun recording any audio. Even then, it seems unlikely that audio would be conclusive evidence of an alleged murder.
At least part of the search warrant indicated that police may not have had a full understanding of how the Echo worked.
"The Amazon Echo device is constantly listening for the 'wake' command of 'Alexa' or Amazon,' and records any command, inquiry, or verbal gesture given after that point, or possibly at all times without the 'wake word' being issued, which is uploaded to Amazon.com's servers at a remote location," the affidavit read in part. "It is believed that these records are retained by Amazon.com and that they are evidence related to the case under investigation."
That allegation — that the Echo is possibly recording at all times without the "wake word" being issued — is incorrect, according to an Amazon spokesperson. The device is constantly listening but not recording, and nothing is streamed to or stored in the cloud without the wake word being detected.
Amazon, for its part, has refused to comply with the warrants, according to court records. A company spokeswoman said she could not comment on this specific case.
"Amazon will not release customer information without a valid and binding legal demand properly served on us," a company spokeswoman said in an email. "Amazon objects to overbroad or otherwise inappropriate demands as a matter of course."
The case and its implications are reminiscent of one earlier this year, in which the FBI demanded Apple's help in cracking an iPhone used by a gunman in the deadly San Bernardino terror attack last December.
Apple refused to comply, and the FBI ended up paying professional hackers to crack the phone.
The ensuing debate drove a wedge between Silicon Valley and Washington, as the tech industry, already wary of government surveillance, rushed to rally behind Apple.
Amazon joined Microsoft, Google and a dozen other tech firms when it filed a legal brief supporting Apple's position in March. "[The] government's order to Apple exceeds the bounds of existing law and, when applied more broadly, will harm Americans' security in the long run," the filing said.
In the midst of that public fight, Amazon Chief Executive Jeff Bezos said the firm was among the many tech companies backing up Apple — and that they were embracing technology that would make it difficult for government officials to access any personal information on its devices, even when those authorities have a warrant.
A Bentonville police spokesman did not return a call requesting comment Tuesday.
Bates, who was charged with first-degree murder, pleaded not guilty in April and has been out on bail, court records show. His trial is set to begin in 2017.
Bates' defense attorney, Kimberly Weber, told the Information she was alarmed by the police request of Amazon, which she viewed as an invasion of her client's privacy.
"You have an expectation of privacy in your home, and I have a big problem that law enforcement can use the technology that advances our quality of life against us," Weber told the news site.
Undeterred by Amazon's refusal to turn over Bates' Echo data, detectives sought the help of a far closer source: the Bentonville utilities department.
According to police records, a city utility billing and collections manager told detectives that the night of Collins' death, 140 gallons of water were used at Bates' home between 1 a.m. and 3 a.m., an amount of water usage that exceeded all other periods there since October 2013.
"In comparison, while all four [men] were together earlier that evening, they never used more than 10 gallons of water in an hour," police reports said. "The amount of water used between 0100-0300 hours was consistent with spraying down the back patio area, which may have resulted in the wet concrete patterns observed on the morning of November 22nd."
The utility department's source? Each home in Bentonville was on a smart meter, police were told, to measure and record the exact consumption of electricity and water every hour.
Wang writes for the Washington Post.