Greg Sanders: For the record, I really like having a penis.
David Hodges: You know, you and me, we're not the marrying kind. The intricacies of our nature can't be understood by just one woman.
Gil Grissom: Would you close the door, please?
[David Hodges shuts the door with himself still in the office.]
Gil Grissom: From the other side.
Nick Stokes: There's a sucker born every minute.
Gil Grissom: Yep, and they all come to Vegas.
[To a room full of dead corpses, after Holly Gribbs was frightended into hysterics.]
Gil Grissom: You assholes!
Grissom: He's a highly functional autistic with superior right brain abilities.
Nick: Sounds kind of like you.
Catherine Willows: I just realized that you and I have a very healthy relationship.
Gil Grissom: We do?
Catherine Willows: Well, when we have a problem, I don't paint Greg Sanders in latex and stick a straw up his nose.
Gil Grissom: Good. He'd probably like it.
Greg Sanders: I'm like a sponge: I just absorb information.
Gil Grissom: I thought that was my line.
Greg Sanders: I know - I absorbed it.
Gil Grissom: Concentrate on what cannot lie - the evidence.
Answer: He doesn't have the authority to arrest him - when anyone is arrested in the show, a police officer does it. Also he tells Ty that he is going to be submitting his case findings to Ty's insurance company, who would no doubt contact the IRS, who then would have him arrested for fraud etc.