I agree that news articles shouldn't speculate on motives and whether or not a shooting was proper in the first few days (with the possible exception of a neutral expert on these issues, such as the excellent copinthehood.com).
Nevertheless, "officer shoots X" is at least as factual and without spin (unless X is "victim" or some kind of loaded word).
OP wasn't about news articles, anyway. In this context, the use of OIS from a precinct press release (i.e., a document not from a neutral observer, but from a representative of one of the involved parties) looks like an attempt to pre-emptively disclaim even the possibility of responsibility, which may or may not exist in any particular case.
Calling it an "officer-involved shooting" (should have a hyphen!) in an initial report restricts the scope to a just-the-facts-as-we-know-them-m'am style. Even from the headline I know: 1> where (Fremont), 2> Fatality, 3> cop was there. Hopefully the first paragraph tells me who shot whom and some macro facts.
But in an early article or "hot take" it's rarely clear if, for example, a cop used excessive force, or poorly pressured someone under stress so they took their own life; if there was legitimate responsibility etc. The passive voice here preserves the "innocent until proven guilty" position.
If the cop is later convicted of murder I would hope that a subsequent news article would be more definite ("officer XXX convicted of murder") or alternatively "Letter: distraught father wanted suicide to be a spectacle"
In fact this is why I am generally uninterested in "news" -- the amount of actual data in these early articles is usually quite small. If people are still talking about it a week later, perhaps it's worth learning about.