BOSTON — On commencement day at Northern Michigan University, some students protested the speaker, Gov. Rick Snyder, and his handling of the water crisis in Flint. While some students outside the event carried signs against him, students inside the hall simply — and silently — turned their backs on him as he spoke.

Protests at college commencements are almost a rite of spring, and this graduation season is no different. Some of the demonstrations this year have shapeshifted into actions more subdued than those of just a few years ago. Some are small events within larger ceremonies. And silence as a protest tactic is being used to make a point without ruffling too many feathers.

At Northern Michigan, the university’s president, Fritz Erickson, appeared pleased with the outcome. In a statement, he said he appreciated that the governor, a Republican, still came, despite advance word that he would be met by protests. He said he was proud that the students had been respectful.