US police are increasingly using geofence location warrants and reverse search warrants to obtain user data from tech companies like Google, raising concerns about privacy and the potential for abuse. These warrants allow police to collect data on individuals who were in a specific location at a certain time or who searched for specific keywords. The use of these warrants has increased significantly in recent years, with Google receiving over 11,000 geofence location warrants in 2020. This trend has sparked debate about the need for stronger privacy laws and regulations on law enforcement's access to user data.