Cruz seems to have a very esoteric interpretation of the question before the Senate yesterday:

“Importantly, there are two types of jurisdiction: mandatory and discretionary. With mandatory jurisdiction, the tribunal must hear the case; with discretionary jurisdiction, the tribunal can decide whether to exercise its legal authority to hear the case. For example, the vast majority of the Supreme Court’s caseload arises on discretionary jurisdiction—it has the authority to hear most cases, but it doesn’t have to do so.

“And nothing in the Constitution makes the Senate’s impeachment jurisdiction mandatory. “Sole power” means “sole power”—the Senate can decide whether to hear the case.

“The present impeachment is an exercise of partisan retribution, not a legitimate exercise of constitutional authority.”

In other words, Cruz seems to have skipped to the conclusion of the impeachment trial. “On the merits, President Trump’s conduct does not come close to meeting the legal standard for incitement — the only charge brought against him,” Cruz writes. Having reached that conclusion before the impeachment trial began, Cruz works backward to argue that the trial is unconstitutional.