Both cases also could have profound long-term ramifications, potentially giving presidents sweeping new protections from investigations, at least while they are in the White House.
The Trump administration is seeking to give employers and universities a broad right to claim a religious or moral exemption from the Obamacare requirement that they offer free birth control through their health care plans. The opt-out would expand a narrower religious exemption offered by President Barack Obama's administration as part of the Affordable Care Act.
Although the case could turn on technical questions of federal administrative law, its symbolic and cultural implications loom much larger. And a high court blessing for Trump's opt-out could mean that tens of thousands of woman would lose access to free contraceptives.
The administration is arguing alongside the Little Sisters of the Poor, an order of Catholic nuns that says it is trying to avoid having its employee health-care plan "hijacked" to provide birth-control coverage.
As in many of the court's cases, Chief Justice John Roberts may wield the pivotal vote. During arguments in May, he said the Trump exemption "reaches far beyond" the Little Sisters' concerns. "In other words, not everybody who seeks the protection from coverage has those same objections," he said.
The contraceptive clash is one of two remaining religious-rights cases. The court also will decide whether to extend a previous ruling that shields faith-based organizations from discrimination claims by ministers. Two Roman Catholic grade schools in Southern California say that exemption should also apply to teachers who carry out important religious functions.
In the 2012 case, Roberts said a religious group has a constitutional right to "shape its own faith and mission through its appointments." That unanimous decision threw out a suit by a grade-school teacher who had completed a required theology program and been given the title "minister of religion."
Federal appeals court panels said the circumstances were different in the latest cases because the instructors held the title of "teacher," lacked any special religious training and didn't hold themselves out as religious leaders or ministers. The schools are being accused of age and disability discrimination.