Nicolas,you bring up some very interesting & plausible thoughts. Uncontradicted evidence at trial showed that Rudy was continually extremely abusive to Della & a police recording of Della at the hospital (also at trial) just prior to her death demonstrated that she said if she was ever found dead that "Rudy killed me".  Lets not forget about that serial rapist Greg Poindexter that was preying & raping Alaska Native females immediately around that timeframe. He was eventually convicted & shown to have homicidal ideations by trained professionals. May I add that he attacked & beat a DOC guard while in custody shortly after they arrested him, & the guard couldn't return to work due to extensive injuries. Poindexter lived on the next block over from where Della's body was discovered. Both were considered alternative suspects at trial after extensive evidence was presented showing their propensity of committing the murder.  These other "petty criminals" were in fact very dangerous people!