I was reading THE KANSAS CITY STAR, which I suppose is an American online paper.
I came across an article where the following sentence appeared.
“I do find that the victims in this case, in particular, were more an aggressor than a participant in the criminal conduct,”
My question: “the victims” is a plural, (two young girls). Is it acceptable to use a singular “an aggressor, a participant” to refer to the girls?
Or is it not problematic because an aggressor in this case means just anyone that is aggressive?
The sentence in question was one that was spoken by the judge in the trial. It was simply quoted by the newspaper. It is not a sentence that originated in the mind of an American journalist. If you search Google using that quotation, you will see that all the newspapers that are reporting on this, whether or not they are in the United States, contain that sentence -- precisely because it is a key quotation.
I agree with you that the judge's use of the singular in subject-complement position is a little jarring, given his use of the plural ("the victims") in subject position, which was necessary. I also see that at least one other newspaper reporting on the trial has changed the singular to the plural in reporting about the sentence. It gives the original and then alters the original when speaking of it:
The case attracted widespread attention this week after the Kansas City Star obtained a transcript of the sentencing hearing. On Monday, the newspaper published an editorial saying that Gibbens “made a serious mistake” by setting Soden’s sentence so low and that he shouldn’t be a judge.
“If Gibbens believes that child sex abuse victims are somehow aggressors, he doesn’t belong on the bench,” according to the paper’s editorial board."
source: The Washington Post
Again, the judge's sentence (which pertained to his sentence, in a difference sense of "sentence" ) occurred in spoken English, where one will often be disappointed if one expects to see or hear absolute grammatical perfection. I think it makes sense that he made this mistake insofar as, if I understand the case correctly, the girls were jointly selling themselves online -- as a package deal.