If that were true, then every finding of fact by a court, every murder sentence, every divorce decree, every small claims award, every speeding ticket fine, all of it, would be judicial activism. In fact, a ruling by the court that a fetus is a human would be in its way sounder than a guilty sentence in a murder trial, since there is no real doubt that a fetus is not human, but the murderer was only convicted beyond a reasonable doubt. Seriously, can you give me any scientific evidence that a fetus is not a human baby?
Saying that a fetus is a person and should not be murdered is no more judicial activism than if a court decreed that women named Linda are human and should not be murdered.
We're talking past each other. You're speaking biologically - of course a human fetus is human, that's established. I'm talking about its personhood being established in law, which is a completely different question.