  The sectional category of a subgroup inclusion $H \hookrightarrow G$ can be
defined as the sectional category of the corresponding map between
Eilenberg--MacLane spaces. We extend a characterization of topological
complexity of aspherical spaces given by Farber, Grant, Lupton and Oprea to the
context of sectional category of subgroup inclusions and investigate it by
means of Adamson cohomology theory.
