OTTAWA—Craig and Marc Kielburger accused a parliamentary committee of engaging in a political trial Monday as its members grilled the brothers over WE Charity’s operations, including its since-cancelled deal to run a federal program for student volunteers. The heated exchange had the Kielburgers accusing political parties of trying to score points at the expense of children around the world, even as they faced pointed questions from members of the House of Commons ethics committee about their own activities. Those included how the Liberal government and WE came to an agreement for the charity to run a multimillion-dollar program designed to cover the education costs of students who volunteer during the COVID-19 pandemic, and the state of WE today. The brothers were also asked to tally how much they paid Prime Minister Justin Trudeau and members of his family to speak at different WE events over the years, and to respond to allegations …