Democratic White House contenders united in backing the impeachment inquiry of Republican President Donald Trump on Wednesday, but differed over the wisdom of imposing new taxes on the wealthy and how to expand healthcare coverage for Americans. At the fifth debate in the Democratic race to pick a challenger to Trump in the November 2020 election, candidates said the president’s efforts to press Ukraine to investigate former Vice President Joe Biden were an example of the administration’s corruption. “We have to establish the principle that no one is above the law, we have a constitutional responsibility and we need to meet it,” said U.S. Senator Elizabeth Warren, an early supporter of Trump’s impeachment. The Democratic-led House of Representatives has launched an impeachment inquiry into Trump’s bid to get Ukraine to investigate Biden and his son Hunter, who served on the board of Ukrainian gas company Burisma. The candidates said Trump had forced lawmakers to hold him accountable. “The constitutional process of impeachment should be beyond politics and it’s not part of the campaign. But the president’s conduct is,” said Pete Buttigieg, mayor of South Bend, Indiana. Biden said as president he would leave it to the Department of Justice to decide whether Trump should be prosecuted for his actions. “If that was the judgment, that he violated the law, and he should be in fact criminally prosecuted, then so be it. But I would not direct it, and I don’t think it’s a good idea that we mock, that we model ourselves after Trump and say: ‘Lock him up,’” he said. The Democratic debate comes just 11 weeks before the first nominating contest in Iowa, on Feb. 3, raising the stakes for the 10 participants hoping for a chance to make an impression with voters before time runs out. The Democratic White House race has featured a three-way battle at the top of recent national polls between moderate Biden, the former U.S. vice president, and progressive leaders Warren and U.S. Senator Bernie Sanders.