Crime Fighting Ninjas

You've probably seen an episode of Criminal Minds before, right? Or maybe you're a CSI kinda guy. Nevertheless, most likely you've seen a similar crime-fighting show that takes you behind the scenes of an investigation and flashes fancy gadgets and tools that make us all want to be super awesome crime fighting agent ninjas.

So here's my question: how accurate are these tv shows? Do crime units actually measure the angle at which a gunshot was fired, or is that all just bs? I'm sure all those special techniques and tricks they use are real, but to what extent are they accurate and how often are they used?

Anyway, Happy August!