Continuity mistake: When Brass calls Dr. Ray and gets his voicemail instead, Brass raises the phone to his ear twice. (00:02:00)
Continuity mistake: Near the start, when Ray is showing the photograph of Madeline with the security guard to passersby asking if they've seen her and also when he shows it to Nick, we can see the photo Ray is holding out in the wide shots, but in the two closeups of the photograph it's actually a different photo. Then later, when Ray shows the photo to Madeline's mother it's the same as the one from the closeup earlier.
Continuity mistake: When Nick asks Dr. Ray what he's doing out on the Strip instead of at their crime scene, and Ray shows him the photograph of Madeline Briggs, his hand moves from the top of the photo to the bottom in consecutive shots. (00:03:20)
Continuity mistake: When Hodges shows Dr. Ray and Nick the information from Dede Chase's cell phone, Ray's arms change position between shots from the tabletop in front of him to crossed across his chest. (00:08:55)
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.