Greek and Roman Origins Both Greek and Roman origins of law are contributed to US Constitution today. Direct democracy, citizen participation, republics, and checks on power all originated from Ancient Greek and Romans. All of these topics played an immense role in creating the US Constitution. Democracy began in Ancient Greece. Direct democracy, where citizens directly participate with the government, required citizens to attend assembly, sit on juries, and make law. This ensured that each citizen participated in government. The Greek also determined that “tyranny is illegitimate,” which ensured that a tyrant can not take complete control nor lack concern for the welfare of citizens. Greek origins also ensured that each person had rights.