Kernrechtsfrage
Whether the challenge to the cantonal investigating judge's letter was admissible as a complaint under Art. 214 PPF or as a federal criminal-law appeal.
Extrahierter Entscheid
The filing was inadmissible because Art. 214 PPF concerns acts or omissions of the federal investigating judge, not decisions by cantonal magistrates; a criminal-law appeal would have been the relevant remedy, subject to exhaustion of cantonal remedies.
Extrahierte Begründung
The challenged communication was issued in a cantonal criminal matter and did not fall within the scope of Art. 214 PPF. For cantonal decisions, only an appeal in criminal matters under Art. 78 LTF is available after cantonal remedies are exhausted.