LONDON—Britain should not engage in free trade with countries that abuse human rights, but proposals that the country’s courts should decide whether genocide has been committed by trade partners is flawed, foreign minister Dominic Raab said. Last week, Raab said Britain would introduce new rules for its companies to try to prevent goods linked to China’s Xinjiang region entering their supply chains. Some British lawmakers want to go further and are due to consider proposals passed in the upper house of parliament that would give courts the power to stop free-trade agreements with countries if they consider them to have committed genocide. “The bar is being set incredibly high,” Raab told BBC television on Sunday. “I mean, frankly, we shouldn’t be engaged in free-trade negotiations with countries abusing human rights well below the level of genocide.” He said the proposals in parliament were problematic because Britain’s High Court did not …