There were many tense moments Tuesday as the nine Supreme Court justices grilled the plaintiffs challenging the Biden administration’s student loan forgiveness plan and the government attorney defending the policy.

The Supreme Court agreed to hear two challenges against President Joe Biden’s unprecedented plan to cancel up to $20,000 in student debt for tens of millions of Americans. Six Republican-led states brought one lawsuit against the forgiveness plan, and conservative advocacy organization, the Job Creators Network Foundation, backed the second. Both accuse the president of overstepping his authority.

While the justices heard oral arguments, hundreds of student loan borrowers from around the country gathered outside the court in support of the president’s plan, with signs bearing messages such as “Death to student debt” and “Student debt cancellation is legal.”