He suspended habeas corpus, which prevents the government from jailing someone without specific charges.
A little side note for you: Their movement was never very organized, but it was influential. Peace Democrats were the naysaying chorus to Lincoln’s war aims reunion and emancipation. They took great rage at the ways Republicans chose to raise money and men to fight the war, including the nation’s first income tax, conscription and issuance of paper money. They were enraged that Lincoln, with Congress’s blessing, had suspended habeas corpus nationwide, essentially declaring martial law throughout the country.
But there was a down side....Rich men started paying poor people to join the army for them so they didn't have to fight. That's why the Civil War became know as <em>"A rich mans war,And a poor mans fight"</em>
Anyways hope I <u>helped!!!</u>