We provide a structural analysis of the space of functions of bounded deviatoric deformation, \(\textrm{BD}_{\textrm{dev}}\) , which arises in models of plasticity and fluid mechanics. The main result is the identification of the annihilator and a rigidity theorem for \(\textrm{BD}_{\textrm{dev}}\) -maps with constant polar vector in the wave cone characterizing the structure of singularities for such maps. This result, together with an explicit kernel projection operator, enables an iterative blow-up procedure for relaxation, homogenization, and integral representation problems, allowing for integrands with explicit dependence on u as well as \({{\mathcal {E}}}_d u\) . Our approach overcomes several difficulties as compared to the \(\textrm{BD}\) case, in particular due to the lack of invariance of \({{\mathcal {E}}}_d\) under orthogonalization of the polar directions.