I presented this theory last year when Rigsby wasn't a suspect. The episode where Jane drank the hallucinogen tea made me think that what we are watching is Jane's alternate reality. 

What if:   1. Jane's wife was Laurelei (maybe she was divorcing him)
               2. Jane's wife and child die in a drunk driving accident with Wayne Rigsby
               3. Jane was also in the accident, which ended in an explosion
               4. Jane has had to interact with the medical examiner and investigation
               5. Sister Theresa Lisbon is praying for his lost soul (hence the cross that is
                   always around her neck)
Subtle Clues
               * Toy red corvette on table when Jane investigates the death of Laurelei's sister
               * Toy red corvette then shows up on Rigsby's desk in another episode
               * While Mashburn and Jane are joyriding in the yellow corvette, Jane was asked if 
                 he liked the car. Jane replied that the car was the wrong color
               * When Jane sees the body of Laurelei,, he says that she deserved it
               * Episode where Rigsby was in car accident and blood was streaming down his
                 face
               * Scotch bottle with red tip shown in another episode