Conservative justices holding the Supreme Court's majority seem likely to sink President Joe Biden's plan to wipe away or reduce student loans held by millions of Americans. In arguments lasting more than three hours Tuesday, Chief Justice John Roberts led his conservative colleagues in questioning the administration's authority to broadly cancel federal student loans because of the COVID-19 emergency. The plan has so far been blocked by Republican-appointed judges on lower courts. It was not clear that any of the six justices appointed by Republican presidents would approve of the debt relief program, although Justices Brett Kavanaugh and Amy Coney Barrett appeared most open to the administration's arguments. Biden's only hope for being allowed to move forward with his plan appeared to be the slim possibility, based on the arguments, that the court would find that Republican-led states and individuals challenging the plan lacked the legal right to sue. That would allow the court to dismiss the lawsuits at a threshold stage, without ruling on the basic idea of the loan forgiveness program that appeared to trouble the justices on the court's right side. Roberts was among the justices who grilled the Biden administration's top Supreme Court lawyer, Elizabeth Prelogar, and suggested that the administration had exceeded its authority with the program. Roberts pointed to the wide impact and expense of the program, three times saying it would cost “a half-trillion dollars.” The program is estimated to cost $400 billion over 30 years. “If you're talking about this in the abstract, I think most casual observers would say if you're going to give up that much ... money. If you're going to affect the obligations of that many Americans on a subject that's of great controversy, they would think that's something for Congress to act on,” Roberts said. Kavanaugh suggested that the administration was using an “old law” to unilaterally implement a debt relief program that Congress had rejected. He said the situation was familiar: "in the wake of Congress not authorizing the action, the executive nonetheless doing a massive new program.” That, he said, “seems problematic.” Kavanaugh noted that the administration was citing the national emergency created by the coronavirus pandemic as authority for the debt relief program. He argued that some of the “finest moments in the court's history" have been "pushing back against presidential assertions of emergency power.” At another point, though, Kavanaugh suggested there might be a better fit between the program and the authority provided by Congress than there was in other cases in which the court's conservative majority ended other pandemic-related programs, including an eviction moratorium and a requirement for vaccines or frequent testing in large workplaces. Prelogar told the justices “defaults and delinquencies will surge above pre-pandemic levels" if the program isn't allowed to take effect before a three-year, pandemic-inspired pause on loan repayments ends no later than this summer. "The states ask this court to deny this vital relief to millions of Americans,” she said. The administration says that 26 million people have applied to have up to $20,000 in federal student loans forgiven under the plan. “I’m confident the legal authority to carry that plan is there,” Biden said Monday. The president, who once doubted his own authority to broadly cancel student debt, first announced the program in August. Legal challenges quickly followed. Republican-led states and lawmakers in Congress, as well as conservative legal interests, are lined up against the plan as a clear violation of Biden's executive authority. Democratic-led states and liberal interest groups are backing the administration in urging the court to allow the plan to take effect. The administration says a 2003 law, commonly known as the HEROES Act, allows the secretary of education to waive or modify the terms of federal student loans in connection with a national emergency. The law was primarily intended to keep service members from becoming worse off financially while they fought in wars in Afghanistan and Iraq. Nebraska and other states that sued say the plan is not necessary now to keep defaults roughly where they were before the pandemic. The 20 million borrowers who would have their entire loans erased would get a “windfall” leaving them better off than before the pandemic, the states say. “This is the creation of a brand new program, far beyond what Congress intended,” Nebraska Solicitor General James Campbell said in court Tuesday. Dozens of borrowers came from across the country to camp out near the court on a soggy Monday evening in hopes of getting a seat for the arguments. Protesters gathered outside the high court as justices heard arguments in the legal fight over Biden's plan for debt relief. Student government leaders from Big 12 universities who were in the nation's capitol meeting with legislators today about higher education affordability and access to mental health spoke to The Associated Press about the need for student loan debt relief. A group of students from the University of Texas at Austin said that they were in solidarity with the protesters, and told of the importance of student loan relief. Patrick Chaton, a student from the University of Texas at Austin said: "For me, it's going to mean more than just my education. It's going to be more to my parents who honestly were quite scared when I wanted to go to Austin. They felt like it was unaffordable. But student loans have really helped me at least. You know, being a low-income student helped me take classes, put myself out there, and be involved in organizations like student government." When asked about older Americans who express concern that paying off student debt is unfair to those who paid off their loans, Isabel Agassi said, "I think that because of inflation, the cost of education for college students now is significantly more than it was at that time." Libby McTaggart said; "I would say to older Americans to remember that there are people there, young people who simply don't have the generational wealth, don't have the means and don't have the resources to pay their college in full debt free. And as the cost of college continues to outpace inflation, it's critical that support is given to those people who don't have the means to repay their debt right away. Earlier programs halted by the court were billed largely as public health measures intended to slow the spread of COVID-19. The loan forgiveness plan, by contrast, is aimed at countering the economic effects of the pandemic. The national emergency is expected to end on May 11, but the administration says the economic consequences will persist, despite historically low unemployment and other signs of economic strength.