See, this is why I was saying I find it hard to explain. Lots of people lie to police, file a false statement, even, and don't get arrested. If they did, we would really have an overpopulation problem at prisons. I think this is a charge they can use, if they so choose, depending on how much the lies affect the investigation. Kind of like when a person gets pulled over for speeding, sometimes they get a warning. It is an option that is available, but doesn't have to be enforced. In the case of Casey, they chose to enforce it, as this is a serious situation, and they want to press as many charges as will stick against her, and probably to use as a lever to get accurate information out of her. On the other hand, arresting this deputy because he lied, what do they have to gain by that? They fired him, point made. JMO
Lanie