50yr old arraigned in juvenile court for rape/muder 34yrs later???

The rape murder of an 82 year old woman that was commited 34 years ago appears to be solved. This is paraphased from the LA Times 9/11/09. A Los Angeles man was stopped for a routine traffic violation and it was dicovered that his DNA matched that at the crime scene (I have no idea why DNA would come up in a trafic stop??).

Horible, horrible crime but here is the conundrum: the rape/murder was commited in 1975. At the time the suspect was 16 years old, a juvenile. He is now 50 but is being arraigned in a LA county  juvenile court instead of adult court.

This begs a ton of ethical, moral and legal questions. I’m not sure I quite understand the intent of the courts. I could use your feedback,

Thanks, 54