That would be ideal, but the reality is that many judges make decisions, to significant degree, based on ideology.
Of course there is no way to prove what someone's motive or state of mind is, but a few observations: 1) Many people think this is plainly true, 2) many votes by Supreme Court Justices can be predicted based solely on the politics of the issue, and with no knowledge of the facts or law, and 3) the Republicans in the Senate currently openly claim that Justice is an ideological job and therefore they won't vote for a Democrat's nominee.
Judges are human beings; we shouldn't hold them to unrealistic standards or we will be shutting our eyes to the realities of how and when justice succeeds and fails. Some are more ideological, some less; some inject ideology more intentionally, some more unconciously based on biases and assumptions.
I once attended a speech by a legal scholar who advocated doing away with juries, and all their human unreliability and flaws, and relying instead on the impartial wisdom of judges. An experienced litigator leaned over to me and whispered, 'judges put on their pants one leg at a time, just like everybody else.'
> Scalia was focused on a strict interpretation of the Constitution.
He said he was, but I've yet to see evidence that it was true. IMHO, he was strict about things he didn't like and flexible about those he did (e.g., Citizens United).