Question:

How can the state of a document be changed, without it going through a workflow?

Answer:

This can be easily & quickly done in Vault by creating a User Action.

1. Go to Admin --> Configuration --> Document Lifecycles --> States --> {Current state that the document is in}.
   
   

2. After clicking the State, click the User Action tab.   
   
   

3. Click Edit.
4. In the drop-down, choose Change State to.
5. In the next drop-down, choose the desired document state.
   
   

Related Documentation:

Vault Document Lifecycle Documentation: User Action Help