https://www.vice.com/en_us/article/43kga3/amazon-is-coaching-cops-on-how-to-obtain-surveillance-footage-without-a-warrant

When police partner with Ring, Amazon’s home surveillance camera company, they get access to the “Law Enforcement Neighborhood Portal,” an interactive map that allows officers to request footage directly from camera owners. Police don’t need a warrant to request this footage, but they do need permission from camera owners.

Emails and documents obtained by Motherboard reveal that people aren’t always willing to provide police with their Ring camera footage. However, Ring works with law enforcement and gives them advice on how to persuade people to give them footage.