 Petrescu-Comnen spearheaded the PNL opposition, especially so during March 1920, when he filibustered against the appointment of Nicolae L. Lupu as Interior Minister.He was also noted for proposing legislation that made striking illegal, pressuring the Vaida-Voevod cabinet to look into allegations of Bolshevik influence inside the Socialist Party of Romania.Despite PNL protests and support from the far-right National-Christian Defense League, Petrescu's law was not passed.