A panel of sceptical US appeals court judges grilled a government lawyer yesterday on President Donald Trump’s use of an emergency authority to impose sweeping tariffs against countries around the world. The federal Court of International Trade blocked most of the duties from taking effect in May but the US Court of Appeals put the ruling on hold to consider the case. Brett Shumate, representing the Trump administration, defended the president’s authority to impose the tariffs under the 1977 International Emergency Economic Powers Act.