emergency
He has been governing by emergency decree under the provisions of the constitution.

divine, papal, presidential, religious, royal
government
court, judicial (esp. AmE)
divorce
consent (AmE)

issue, pass
The president issued a decree prohibiting trade unions.

sign
enforce
Local inspectors helped enforce presidential decrees.

revoke
govern by, legislate by, rule by
The general will rule by decree until a general election.

in a/the decree
In an emergency decree, the government banned all rallies.

decree on
a decree on property rights

Decree is used with these nouns as the subject:
fate