Whether X.________ could still participate as private plaintiff for criminal and civil claims after earlier statements refusing to file a complaint.
Yes. The earlier refusals concerned only the criminal complaint under the former cantonal procedure, not a waiver of later participation under the CPP.
The December 2010 statements were made before the CPP entered into force and had to be read under the former Vaud code; they were only a renunciation of filing a criminal complaint. Because the offence was prosecuted ex officio and X.________ expressly declared before closure of the preliminary proceedings that he wished to participate, he had to be recognized as a private plaintiff.