You're just wrong. Although the obvious assumption is that someone did it, and you're almost certainly correct in that assumption, until you can point out who or why you don't know that for sure. The best way to communicate the case efficiently is to put up the facts. Then you ask the questions who and why in the article. People complain about passive voice too much here. Cops get the same treatment as others by passive voice because "13 dead, 6 injured in school shooting" is just as common as "man killed by cop." The phrasing on cops usually separated then more or makes the victim seem less sympathetic, which is the issue, but the passive voice alone is not the problem. In this case, they are not removing a single bit of blame, just presenting what is known as clearly and precisely as possible.