Can I limit which editors can issue a decision?
Yes!
If your journal wants to limit which editors are able to issue a formal decision through Scholastica, you can do so when inviting them to become an editor and you can also do so when editing your Configuration Options later.
Editors' decision permissions have three levels: (1) Cannot draft nor send to author — cannot access or edit the decision draft but can view the final issued decision; (2) Draft only — can access and edit the decision draft but cannot send it; (3) Draft and send to author — can both draft and issue the final decision.
Setting ability to issue a decision during editor invitation
When the admin editor for your journal has followed the steps to invite an editor and is on the "Manage editor viewing permissions" screen, they'll set the editor(s)'s manuscript viewing permissions and can then select if the editor should not be allowed to draft nor issue decisions, only be allowed to draft publication decisions, or draft and issue publication decisions on manuscripts to which they have access. Just select the appropriate radio button and click "Save and close" to confirm that choice.

Setting ability to issue a decision in the journal's Peer Review Settings
If you'd like to update an editor's ability to issue a decision after they've already been invited, the admin editor for your journal can do so by navigating to My Journals > Peer Review > Peer Review Settings > Decision Settings > Publication Decision Permissions.

Adjust the permissions for each editor appropriately to make your desired updates. Then click "Save" to save your changes.
Note: The admin editor can always draft and send decisions
