The Supreme Court on Thursday sided with a teenage girl with epilepsy and her parents who had sued a Minnesota school district, claiming that her school had failed to provide reasonable accommodations, which made it difficult for her to receive instruction.

The case hinged on what standard of proof was required to show discrimination by public schools in education-related disability lawsuits.

In a unanimous decision written by Chief Justice John G. Roberts Jr., the court held that the student and her family needed to show only that the school system had acted with “deliberate indifference” to her educational needs when they sued.

That is the same standard that applies when people sue other institutions for discrimination based on disability.

The school district argued that a higher standard — a stringent requirement that the institution had acted with “bad faith or gross misjudgment” — should apply. Had the district prevailed, the new standard might have applied broadly to all kinds disability rights claims filed under the Rehabilitation Act and the Americans with Disabilities Act.

That argument had unnerved some disability rights groups, which had cautioned that a ruling for the school could make it much harder for Americans with disabilities to successfully bring court challenges.