Creating a tool like this should not be alarming to anyone. Apple does provide user data to police and other law enforcement agencies, but only when presented with a valid warrant. Even in such cases, the company can only share data that is stored in the cloud and cannot give out user data that is stored on iPhones, which are encrypted by default. Apple has handled 14,000 U.S. law enforcement requests in 2017, all sent via e-mail. The company said that all requests were responded to within 20 minutes or so, regardless of the time of night or day. The tool would simplify the process and allow officers of the law to make and track the status of their requests.
For the end-user, this makes very little difference, but for the company, the tool would hopefully simplify the process.