How? Whatever the system is now is clearly not preserving privacy
Have an independent non-profit with strong oversight manage the data. Grant access with a warrant.
The police should show that a crime has likely been committed, and get access to just the data that probably has evidence.
Closed loop systems that require explicit consent to share outside the organization. Flock is like 50x worse than NSA stuff like PRISM that everyone freaked out about.
The Feds have full access to search everything, are no doubt exempt from any transparency on the platform, and ICE is already using it to abuse and intimidate political enemies.
It’s a nationwide surveillance system posing as a local police tool.