Why didn't they go after Horatio's bitch baby mama?

She had motive (and the shooter had no independent motive himself), they had testimony of the shooter and they found the murder weapon in her car. That's more than enough to prosecute, but they didn't have any interest in going hard after her (Horatio keeps treating her like some sort of victim) - complete conflict of interest by Horatio's lab!
Caleigh looked positively giddy when she told the shooter that the woman who ordered the hit will get away with it. And that wasn't the first time they allowed a female murderer to get away with it - for example Alexx's friend.

And as to Kyle, they had more than enough evidence to convict even without the victim's testimony. And he gets away with it too. Funny how Horatio's family is made out of teflon - Stettler should look into it.