Snipping for focus.
Welcome to Websleuths.
Tho your post describes you as a T/C novice, I agree: to date, LE has not released
factual info pointing to identifying a suspect. Or even a person of interest.
Snipping to address part of only one angle: Using knife, not gun?
Not necessarily indicate anything about
income.
Why was gun not used?
If perp planned killings, prior to entering house/apt., seemly likely perp may have considered gunshot
noises & the
unwelcome attention they would have brought in that neighborhood of closely spaced homes & apts. Well, that is, if perp was thinking rationally, as we usu. do here.
Ability to procure gun?
Could perp have bought a
handgun legally?
Purchasing a firearm is subject to
federal law and a federal NICS* background check for sales made thru fed'ly licensed firearms dealers.**
IN. statutes also govern handgun purchases.***
For
private sales in IN, background checks are not required, so a perp may have chosen that route.
Of course, as an alternative to legally purchasing, a perp could "borrow" either w. or w'out owner's permission.
Or might use the time-tested way
stealing a handgun.
If planning to use a handgun to kill or even "just injure" a person, a perp may not give a second's thought to possible prosecution or conviction for handgun law violations.
It's also possible perp had gun w him at the time of killings and may have shown it to one or more victims (brandishing it to encourage silence) but did not fire it.
So much we do not know. At least not yet.
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For lots of tedious, technical details, see:
Both Indiana and Federal laws restrict purchase and possession under certain circumstances. Federal law prohibits possession of firearms for life by those convicted of felonies and for those convicted of misdemeanors involving domestic violence.