Was the Black Dahlia killed by a serial killer?

Almost certainly yes. Over time serial killers usually escalate their crimes. They are seeking more thrills and must get more daring and sometimes foolish just to get the same feelings. The Black Dahlia murder showed this escalation. There were actually 2 other murders that preceded the Dahlia case, one of them was called the 'bathtub murder'. Most experts agree that the Dahlia was put in a bathtub, her body drained of all its blood and then scrubbed clean to leave no trace evidence.