Assume for the sake of argument Roberts voted as he did out of personal concerns rather than sound legal reasoning. Perhaps, for example, some sort of blackmail. How would Cruz or anybody be able to predict the deviation that might result from deliberate tampering? If you read the Cruz recommendation, it does sound like Roberts should have been a reliable conservative vote. Some things are hard to predict. That’s just real life.
Peace,
SR
Historically, Republican Presidents have batted no better than 50/50 picking conservative Supreme Court nominees.
Reagan gave us Antonin Scalia (a conservative), Sandra Day O’Connor (a moderate) and Anthony Kennedy (a moderate on most issues but a far left-wing liberal in any case involving homosexuals).
Bush Sr. gave us David Souter (a liberal) and Clarence Thomas (a conservative).
Bush Jr. gave us Samuel Alito (a conservative) and John Roberts (sometimes conservative, sometimes moderate, sometimes liberal, pretty much depending on which way the wind is blowing).
Democrat Presidents on the other hand always pick reliably far left-wing Justices.
IMHO, the problem has been that ever since Bork, Republican Presidents have tried to pick “stealth” candidates with no conservative record that Democrats can attack. To hell with that. The next President needs to pick reliably conservative candidates with long paper trails of consistently conservative rulings and then fight like hell to get them confirmed. If the Democrats and RINOs join together to block confirmation of a nominee, then the next nominee should be even more conservative.