A leader decides that his country's citizens should be completely loyal to him. he sends undercover police to observe citizens and arrest anyone who criticizes the government. he also jails reporters who write stories that show the government in a negative light

The answer would be: Totalitarianism

In totalitarianism, the Government has complete control on all of the citizens. Totalitarianism Government has the right to punish and execute all of the citizens that dare to disobey Government orders, or even for talking about the government in a negative way