Four years after the 6 January attack on the Capitol, Donald Trump has promised he will pardon hundreds of his supporters who were convicted over their roles in it. This comes after Joe Biden gave an unconditional pardon to his own son, Hunter, for federal crimes of which he had been convicted. This week, Jonathan Freedland speaks to Kimberly Wehle, a constitutional law expert, about whether the presidential pardon has become nothing more than a perk of the job to be used for a president’s personal convenience