Officials with the Hallandale Police Department said the witness was named Alexa -- the smart device sold by Amazon, the Sun-Sentinel reported.
Amazon's Echo and Echo Dot "listen" for a "wake word" that signals when the user wants something. For example, play a song, ask what the temperature is outside or answer a question. Police believe Alexa -- nicknamed for its wake word -- might have recorded what happened when Silvia Galva, 32, argued with her boyfriend, Adam Reechard Crespo, 43, on July 12, the Sun-Sentinel reported.
According to a search warrant obtained a month after Galva's death, investigators want to find out if the voice-controlled smart device heard anything that night, the newspaper reported.
“It is believed that evidence of crimes, audio recordings capturing the attack on victim Silvia Crespo that occurred in the main bedroom ... may be found on the server maintained by or for Amazon,” police wrote in their probable cause statement.
According to police, on July 12, Crespo grabbed Galva by the ankles and pulled her off the bed in their Hallandale Beach condominium, the Sun-Sentinel reported. According to an arrest report, Galva grabbed a spear at the foot of the bed to keep herself on the bed.
According to a police report, the force used by Crespo to pull Galva off the bed caused the spear's shaft to break,
Crespo told police he heard a snapping sound and saw Galva was impaled by a 12-inch, double-sided blade, the Sun-Sentinel reported.
Crespo was charged with murder without premeditation, according to an arrest report by the Broward County Sheriff's Office.
Amazon turned over multiple recordings, but officials with the police department of the State Attorney's Office have not said what was on them.
"We did receive recordings, and we are in the process of analyzing the information that was sent to us," Hallandale Beach Police Department spokesman Sgt. Pedro Abut told the Sun-Sentinel.
Amazon spokesman Leigh Nakanishi told the newspaper the Echo devices only record short bursts of statements and are not eavesdropping on private conversations.
"By default, Echo devices are designed to detect only your chosen wake word," Nakanishi told the Sun-Sentinel.
“Alexa” is the default word that activates the device, though consumers can change it to “Amazon, Computer, or Echo.”
Only after the wake word is uttered does the device begin to listen and record, Nakanishi said.
"No audio is stored or sent to the cloud unless the device detects the wake word," Nakanishi told the Sun-Sentinel.
According to Amazon.com, for a device to start recording, the user has to rouse the device by saying the wake word, "Alexa," or a word the owner changes it to, like Amazon, computer or Echo.
"Only then does the device begin recording and sending your request to Amazon's secure cloud," the Amazon website states. "You’ll always know when Alexa is recording and sending your request to Amazon’s secure cloud because a blue light indicator will appear or an audio tone will sound on your Echo device."
Unless someone spoke the wake word, it is unlikely the Amazon device would reveal much information. The Echo also has a mute button that overrides the wake word, according to the newspaper.
It is not the first time Alexa recordings have been sought to solve a murder probe, NBC News reported.
In 2015, prosecutors in Arkansas asked Amazon for access to recordings from an Echo device at the home of James Bates, who was charged in the death of his friend, Victor Collins.
Collins was found dead in Bates' hot tub in November 2015, the Arkansas Democrat-Gazette reported. Court documents said Collins died of strangulation, with drowning as a secondary cause.
Prosecutors said the recordings contained no evidence, and a judge dismissed charges against Bates, NBC News reported
Meanwhile, Crespo is free on a $65,000 bond, according to Broward County court records.
Crespo's attorney, Christopher O'Toole, said he believes the recordings will help his client.
"We want to hear these recordings as well," O'Toole said in an interview with NBC's "Weekend Today" show. "I believe in my client's innocence 100 percent. And I think that these recordings are only going to help us."
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