Scope of general power of attorney in administrative proceedings: refusal to extend representation to unrelated legal matters without unambiguous consent

The Constitutional Court upheld the petition and ruled that the administrative authority violated the parties' rights by treating a party, who had submitted a general power of attorney for a specific legal matter, as represented by the attorney in other unrelated legal affairs without explicit consent. The dispute concerned the procedural validity of extending the scope of a general power of attorney ("in all matters") submitted in one case to other pending or future proceedings, challenging the authority's interpretation of representation limits. The decisive legal basis rests on the Administrative Procedure Act (AVG) 1950 and established constitutional doctrine, which stipulates that a general power of attorney granted for a single right matter does not constitute an unambiguous manifestation of will to use that representative in all further legal matters, thereby prohibiting the authority from automatically extending such representation to other cases.