The Supreme Court enjoys all but free rein in selecting which cases to review. From the end of one term in the summer until the start of the next, on the first Monday in October, the work of the court is to sift through thousands of petitions from parties that lost in one of the federal appeals courts or highest state courts and are eager for the justices to reverse their fate.

The kinds of petitioners favored say a lot about the court’s interests and biases. The Warren court, eager to champion individual rights, chose a large number of petitions from downtrodden people. The Rehnquist court, looking for opportunities to vindicate states’ rights, favored petitions from the states.

The Roberts court has championed corporations. The cases it has chosen for review this term suggest it will continue that trend. Of the 51 it has so far decided to hear, over 40 percent have a corporation on one side. The most far-reaching example of the Roberts court’s pro-business bias was Citizens United v. Federal Election Commission. By a 5-to-4 vote, the conservative justices overturned a century of precedent to give corporations, along with labor unions, an unlimited right to spend money in politics.

Equally striking is that the court reached far beyond what the parties had argued, to make a sweeping change in constitutional law. It could have upheld the right of the conservative nonprofit group to show an anti-Hillary Clinton movie on a video-on-demand service during the primary season  without opening the door to a new era of political corruption.