The cops won't just consume the API. Software developed for the specific task will.
What I imagine is this:
1. The cop uploads a picture of the suspect taken from camera surveillance at crime scene
2. Software displays the mugshots (and names) of PROBABLE matches from the database with confidence %, color coding according to confidence level, and notice of proper use
3. Cop compares man/woman's picture with what's displayed
4. Investigation continues if necessary
What I imagine is this: 1. The cop uploads a picture of the suspect taken from camera surveillance at crime scene 2. Software displays the mugshots (and names) of PROBABLE matches from the database with confidence %, color coding according to confidence level, and notice of proper use 3. Cop compares man/woman's picture with what's displayed 4. Investigation continues if necessary