Receipt of a letter in a replaced envelope

On 29.04.2025 at 12:15, I received a letter from the Senate Department for Justice for the first time, in an apparently sealed envelope. Observation: The outer surface of the envelope was blank — without postage or a postmark. Explanatory hypothesis: An envelope without postage or a postmark cannot have travelled through the regular postal system in this condition; the natural inference is that the original envelope was replaced. Gap in the evidence: Who replaced the envelope, for what reason and with what intent, I cannot establish from the envelope alone; I therefore make no finding under criminal law pursuant to § 206 StGB — that is a matter for the investigating authorities. The letter contained only the return of my complaint against the Berlin Regional Court (Landgericht Berlin) and Tiergarten Local Court (Amtsgericht Tiergarten) addressed to the Senate Department for Justice.