Manifest Duality Invariance for the Partially Massless Graviton

For a special value of the mass, a massive graviton on de Sitter space acquires an enhanced scalar gauge symmetry, and is called partially massless. The partially massless graviton possesses a duality invariance akin to electromagnetic duality. We display this duality in its manifestly local and covariant form, in which it acts to interchange the first order field equations and Bianchi identities of a gauge invariant field strength.