It's a perfect spring evening for baseball and the home town fans are on their feet for their team, behind 3-2 in the bottom of the ninth with their last-best-hope batter at the plate sitting on a full count. The home plate umpire is Chief Justice John Roberts calling balls and strikes. The pitcher throws a fastball right down the middle as the batter looks on. "Strike three, you're out, that's the ballgame," says Umpire Roberts.

Then, a voice over the loud speaker: "The Congress of Fans has just passed a new rule changing the strike zone. The pitch was outside the new strike zone. Therefore, it's a ball. Game on. Resume play Umpire Roberts."

Chief Justice Roberts has compared the job of a Justice to that of an umpire calling balls and strikes. Hence this baseball analogy for the Chief Justice's dissent this week in a case involving constitutional separation of powers. 

Disproving once again that an 8-person Court will always deadlock 4-4 along political lines, the Supreme Court split 6-2 in the case of Bank Markazi v. Peterson. The constitutional principle involved was separation of powers between Congress and the judiciary. It was a case with hard facts. The majority upheld an act of Congress that made it easier for terrorist victims in pending cases to get to assets the Iranian central back was trying to shield. The majority said Congress is allowed to do that. Chief Justice Roberts (joined by Justice Sotomayor) dissented, arguing that Congress crossed the constitutional separation of powers line and was usurping the job of the judiciary by directing the outcome of cases in progress. To the Chief Justice, the flip side of the idea that judges-shouldn't-legislate is the idea that the legislature-shouldn't-judge.

The constitutional ideas of an independent judiciary and separation of powers are parts of the same design. The Supreme Court, Congress and the President have throughout American history pushed each other like three strong-willed neighbors vigilant about their property/power lines. Chief Justice Roberts has taken heat from conservative politicians for upholding the ACA. Yet this Bush appointee did so based on the judges-shouldn't-legislate idea.  In the Bank Markazi case, we can almost imagine the Chief muttering: 'Hey Congress, I didn't cross your legislative power line in the ACA case. So don't cross my judicial power line.'

The case also reminds that America's generational fight with terrorism is intertwined with its Constitutionalism as people navigate constitutional ideas like separation of powers in search of Justice. Law can at best only provide imperfect compensations for great loss. Among those compensations is the reminder that the United States has a tried and true, while never perfect, Constitution. 

That's how we play ball.