What are you talking about? There are several examples of Dem controlled SCOTUS that made controversial decisions.
For example, the controversial Roe vs Wade that intervened in the abortion debate resulted in decades of legal precedence until it was reversed by the recent SCOTUS.
Here was the make up of the 1973 SCOTUS that was incorrectly decided:
Chief JusticeWarren E. Burger - Republican
Associate JusticesWilliam O. Douglas - Democrat
William J. Brennan Jr. - Democrat
Byron White - Democrat
Thurgood Marshall - Democrat
Lewis F. Powell Jr. - Democrat
Potter Stewart - Republican
Harry Blackmun - Republican
William Rehnquist - Republican
Majority: Blackmun, joined by Burger, Douglas, Brennan, Stewart, Marshall, Powell
Dissent: White, joined by Rehnquist
https://en.m.wikipedia.org/wiki/Roe_v._Wade