There are several ways of doing this.
1. Maintain User Status (Customizing OIBS)
2. Catalogs & Codes: Maintain Justified and Not Justified in Catalog D having this in Header tab page. (This is also Customizing).
3. Find an unused text-field in present Notification Tabs, and use this field for feeding Justified or Not Justified.
4. Add Justified or Not Justified at the end of the Notification Title.(QMTXT).
Jogeswara Rao K