There could be a possibility that the murderer (BK is the accused suspect by LE, so will go with that premise that it is "he" for the sake of brevity) might have known beforehand/before the murders were committed that some of the victims' family members had had drug offenses which he could have learned about through public records beforehand/before the murders, and JMO he surmised that:
- Some of the victims' family members having had drug offenses could serve as possible distractions on "motives" as an attempt to obfuscate and to lead LE in other directions/on a wild goose chase/astray "And/Or:"
- The type of murders (stabbing people viciously one on one/one by one in their beds or bedrooms in the dark of the night) looked like a "crime of passion" that could have been committed by one of the four victims' intimate partners or ex partners or some random stalker/incel bent on revenge killings (e.g., someone in one or more of the 4 victims' personal sphere or just outside it) "And/Or:"
- The location of the murders (a college student rental house just off campus but "cheek and jowl" with fraternity/sorority houses) where 3 of the 4 victims lived and the 4th victim spent time, and the area the house was located was rumoured to be a a place to party and the house the victims lived/spent time in was rumoured to be a "party house" where, presumably, many many people's DNA would be present that would seriously complicate LE's ability to "dial in" on one person's DNA that could be the culprit.
So, IMOO, BK planned for and set up multiple versions of some "tell-tale" and/or relatively obvious possible distracting motives in an attempt to deflect from his motives (no one is privvy to) and/or to create a possible "perfect storm" of complex confusion on the motive for the murders in an attempt to "stump" local LE (Moscow PD).
Acknowledging that "motive" in and of itself is not a key component of solving murders and evidence truly is the "go-by" that can be used by the prosecution to prove innocence or guilt on a case by case basis, IMO, the evidence can often be the real "prove-out" that serves as the underlying reasons for motive.
IMOO the above possibilities are the basis(es) for why BK asked LE in PA upon his arrest something along the lines of "Have you arrested anyone else"?
IMO, that was because he thought he had been so thorough and comprehensive in setting up so many possible "ulterior motives" for the murders, that he was actually super surprised that LE "came for him" and so just had to throw further questions towards LE whether they did just come for "him alone" when he was arrested (and accused as the only suspect) when he really thought they would be distracted for so much longer, if not forever, in investigating the murders and identifying suspects.
JMOO, etc. and RIP Ethan, Kaylee, Maddie, and Xana <3, justice is coming