George Mason's David Bernstein wrote a great article for the Cato Institute last week making the necessary point that the Supreme Court's liberals aren't necessarily its most reliable defenders of individual rights. As Bernstein notes, the dissents in D.C. v. Heller presented "the remarkable spectacle of four liberal Supreme Court justices tying themselves into an intellectual knot to narrow the protections the Bill of Rights provides." As he notes, there's also liberal malfeasance on cases dealing with election-related speech, eminent domain abuse, racial classifications, and "hate speech" to keep in mind.
The only thing I would add is that the Court's conservatives aren't exactly eager to take up the slack. As Radley Balko pointed out, Chief Justice John Roberts and Justice Samuel Alito are
judges who defer to police and prosecutors on criminal justice issues, who would put broad restrictions on your ability to sue government agents who have wronged you, and who embrace the Unitary Executive, essentially the belief that when it comes to foreign policy and national security (and a number of other issues), the president's powers are unlimited, absolute, and unchecked by either Congress or the courts. That isn't an exaggeration.
Justice Antonin Scalia, of course, voted the wrong way in Gonzales v. Raich, siding with the majority against California's medical marijuana law. And in his ugly Boumediene v. Bush dissent, Scalia viciously asserted that recognizing habeas corpus for enemy combatants held at Guantanamo Bay "will almost certainly cause more Americans to be killed."
Perhaps it goes without saying, but wouldn't a few genuine libertarians be a nice improvement?