Tip 1: Focus on maximizing each cop's starting stats first, before making evenly skilled cops. A cop with three shooting will be more reliable and more useful more often than a cop with one of each stat, and specialized cops can cover for each other.
Tip 2: Calls are best done with at least two of the required stat, but that still leaves a small chance of failure. Rely on your equipment to succeed until you have enough cops with level three stats.
Tip 3: For calls, you will use negotiation, stealth, strength, speed, intelligence, then shooting from most to least often.
Tip 4: Try and build a roster of cops that complement each other. Once you have enough cops, you'll be able to create shifts similar to the first game. Make sure you've got enough cops to cover each other's stats every day.