Federal Practice Manual for Legal Aid Attorneys: 4.1.10 Defendants
The defendants should be identified with a close eye toward relief. As a rule of thumb, if you seek damages, seek them from the person who inflicted the injury leading to the claim for damages. By contrast, if you seek injunctive relief, you must name the highest-level officials, usually the department heads, since they can offer the most thorough and far-ranging relief. Injunctive relief starts at the top; damages start at the bottom. The bedrock principle is to include as defendants everyone necessary for relief.