Specific properties of one-dimensional pseudorepresentations of groups

We obtain assertions concerning general properties of one-dimensional (not necessarily bounded) pseudorepresentations of groups. In particular, we obtain a quantitative condition on the numerical defect of a given pseudorepresentation which is sufficient for the pseudorepresentation to be pure, i.e., for the restriction of the given pseudorepresentation to every amenable subgroup be an ordinary character of this subgroup.