* Wasn't beating up the deputy reason enough to arrest Cane? Especially when you suspect he's on ongoing danger to the mayor. She could have easily locked him up past the Saturday deadline.
* Why didn't Cane simply shoot Erica after he killed the Mayor? He'd probably get away scot free.
* For that matter, why didn't Cane just keep running? He openly didn't want to kill Rose, showed repeatedly that Rose couldn't catch him if he didn't want her to, and she only caught up the last time because he set up an ambush for her.