MINNEAPOLIS — Members of a deeply conservative Amish community in Minnesota don’t need to install septic systems to dispose of their “gray water,” the state Court of Appeals ruled last week in a long-running religious freedom case that went all the way to the U.S. Supreme Court.

A three-judge panel ruled that the government “failed to demonstrate a compelling state interest” to justify overriding the religious freedom of the Amish families that challenged state regulations governing the disposal of gray water, which is water that’s been used for dishwashing, laundry and bathing, but not toilet waste.

The Swartzentruber Amish in southeastern Minnesota are among the most traditional Amish groups in the country, U.S. Supreme Court Justice Neil Gorsuch noted in a 2021 ruling. It sent the case back to Minnesota courts for reconsideration in light of a high court decision a month earlier in a different religious freedom case. That ruling went in favor of a Philadelphia-based Catholic foster care agency that said its religious views prevented it from working with same-sex couples.

A Minnesota district court in September concluded that the government showed that it had a compelling state interest “of the highest order” in requiring the Swartzentruber Amish to use septic tanks to protect groundwater supplies in the area. The families then appealed again. The Court of Appeals sided with them last week, and sent the case back to the lower court for an order in favor of the Amish.

In 2013, Fillmore County adopted an ordinance requiring most homes to have a septic system for the disposal of gray water. The Amish community sought an exemption “in the name of our Lord,” explaining that their religion forbids the use of such technology. They also offered an alternative used in more than a dozen other states that would allow them to funnel gray water from their homes by pipes to earthen basins filled with wood chips to filter solids and grease from the water as it drains, similar to how a septic system would work.

The Minnesota Pollution Control Agency refused, and filed an administrative enforcement action against 23 Amish families in Fillmore County, threatening criminal penalties, civil fines and even to force them from their homes if they didn’t comply. State officials presented testimony from an expert in court that said the mulch basins would not be as effective and that the mulch would quickly clog with solids and grease, requiring frequent relocating of new mulch pits.

State courts acknowledged that the requirement for septic tanks systems burdened the Amish community’s religious beliefs. The courts also found that septic systems — not mulch basins — would be the least-restrictive means for the Amish families to meet the government’s interest in protecting public health and the environment.

The federal religious freedom law that was at issue in the Philadelphia case “prohibits governments from infringing sincerely held religious beliefs and practices except as a last resort,” Gorsuch explained at the time, urging the Minnesota court and local authorities to swiftly resolve the dispute.

“In this country, neither the Amish nor anyone else should have to choose between their farms and their faith,” Gorsuch said.

The Court of Appeals noted that the Swartzentruber Amish use some technology, but don’t own or drive automobiles, and don’t use telephones, electric lights or modern flush toilets. They supply water to their homes from cisterns and have always prohibited septic systems.

Fillmore County Attorney Brett Corson is hoping to decide in the coming days whether to appeal to the Minnesota Supreme Court. He has 30 days from the ruling to decide.

“We’re just taking the chance to digest the decision and consider what we’re going to do,” he said.