If that were true, there would not be such huge political fights over judges. As it stands, conservative judges tend to vote one way, liberal judges tend to vote another.

That is not the impression my reading about various cases has left me with.

I can't point you to specific cases - I can only say that what has really stood out to me is that the justices do mostly seem to have well-defined interpretive frameworks, and that they work from those.

I can think of an exception, but my experience has generally been that it's the case.