Anyone can enforce or seek to enforce a Deed restriction.

Deed restrictions are contracts between and among all property owners who live in a single subdivision. While your Homeowners Association has taken an active role in enforcing the deed restrictions, any one subdivision property owner may seek to enforce the restrictions against another subdivision property owner.

Let's say you put a black fence around your property, but the deed restrictions say that all fences must be white, you association or even a neighbor can seek to enforce the restriction on record.