Pym's diary shows he viewed Parliamentary legislation as a whole, not just issues of interest to himself; combined with an ability to explain them clearly, it led to his appointment to numerous committees. Since direct criticism of the king was considered treason, the only way to express opposition was by attacking his advisors, using the process of impeachment. Pym argued it was for the Commons to decide guilt or innocence, leaving the Lords only to determine the penalty; this would become significant in his future Parliamentary career.