The series is based on real-life Los Angeles Police Department officer William Norcross. Norcross moved to Los Angeles in 2015 and joined the department in his mid-40s.
Shawn Ashmore was originally brought on as a temporary love interest for Angela. However, his character's popularity, coupled with his chemistry with Alyssa Diaz, promoted the writers to promote him to a main cast member in season 3.
Melissa O'Neil is a very accomplished singer, having won the third season of Canadian Idol (2003) at just 17. In an episode opening, as a reference, Lucy accidentally auditions for American Idol (2002). The judges were on their lunch break when it was filmed, and had no idea of O'Neil's background. Their honest reactions made it onto the scene.
Tim Bradford has the habit of holding a door open and letting who is with him through it first. This wasn't scripted, just a trait that Eric Winter does in real life.
Differs from the normal police-procedural show, with its crime-of-the-week formula, and instead focuses more on the relationships of the characters. Creator Alexi Hawley considers the show "a character show masquerading as a cop show."