By Robert Barnes

It’s time for the conservative justices on the Supreme Court to get to work.

That’s not an accusation of sloth but a reflection of reality. As the court heads into the crucial final weeks of the term, it is apparent that the great majority of remaining decisions will be authored by the court’s most consistent conservatives.

It’s a conclusion drawn from a numbers game that is unique to the Supreme Court and easy enough even for journalists and lawyers, who often joke that they chose their professions on the promise that there would be no math or hard science.

(That said, we’ve been challenged this term. Justice Clarence Thomas dispensed a two-page primer on DNA sequencing, and from a case involving the Internal Revenue Service, there was this:

Tax = 51.71% x [P- ( FV 9 ) x 4.0027]

Fortunately, it did not require solving the equation to understand that the IRS lost.)

Two facts inform the speculation that always consumes court-watchers this time of year.

One, the court divides each term into seven segments called sittings. And two, each justice generally writes at least one majority opinion per sitting.

So at this point in the term, even journalists and lawyers can master a form of Supreme Court bingo that matches the undecided cases from each sitting with the justices who have not written a majority opinion.

For instance, one of the biggest cases of the term — whether the University of Texas may consider race when making admission decisions — is the only case from the court’s first sitting in October that has not been decided.

And Justice Anthony M. Kennedy is the only justice who has not written an opinion from that sitting.

Doug Kendall of the liberal Constitutional Accountability Center looked at the list of remaining cases and came to the same conclusion as others, writing:

“Working through these statistics sitting-by-sitting, Justice Kennedy and the Court’s conservatives stand ready to author some of the most important rulings of the Term.”

Of course, with the composition of this particular Supreme Court, that is something of a truism. But this term’s numbers really underscore the point.

With only two weeks left in the term, the court’s four-member liberal bloc — Justices Ruth Bader Ginsburg, Stephen G. Breyer, Sonia Sotomayor and Elena Kagan — has produced a combined 30 majority opinions.

On the other hand, the court’s four most consistent conservatives — Chief Justice John G. Roberts Jr. and Justices Antonin Scalia, Samuel A. Alito Jr. and Thomas — have produced only 20.

Ginsburg, the senior justice among the liberals, has written nine opinions, more than any other justice. Alito, one of the most conservative, has turned in only three.

(The statistics-gatherers at SCOTUSblog make it particularly easy to play this game at home.)

Only two cases remain from the February sitting, one of them among the most important of the term: the continued viability of a key section of the Voting Rights Act. The case concerns Section 5, which requires federal approval of any voting-law change in certain states and jurisdictions that Congress found had discriminated in the past.

The bad news for those who say the law is still vitally necessary: Only Roberts and Scalia have not written an opinion from that sitting. Both were sharply critical of the law during oral arguments, and Roberts warned in a previous case that Section 5 may no longer meet constitutional muster.

From the March sitting came the court’s marquee cases of the term — the two involving same-sex marriage — as well as a voting-rights challenge to an Arizona law. All four of the court’s liberals have written opinions in noncontroversial cases from that sitting; only Thomas among the conservatives has authored an opinion from then.

Of course, it doesn’t require a scorecard to know that Kennedy probably holds the key to the use of affirmative action in higher-education admissions. (The bigger question is what’s taking so long: The court has decided 46 cases argued after Fisher v. University of Texas.)

Likewise, he was the focus of arguments in the same-sex marriage cases: whether the Defense of Marriage Act unconstitutionally withholds federal benefits from same-sex couples legally married where they reside, and California’s Proposition 8, prohibiting same-sex marriage in that state.

His pivotal role reflects that while Kennedy most often sides with conservatives, he wrote the court’s most recent victory for gay rights and has not been as willing as others on the right to prohibit racial considerations.

But even more-predictable justices are capable of surprise. At this time last year, opponents of the Affordable Care Act would have felt reasonably good about their chances if they’d known that Roberts was writing the opinion. Only once before had he sided with the court’s liberals to decide the outcome of a case.

What will this term’s surprise be?