I know there is an argument about d’roysa. But is there an argument regarding rabbinic issurum that are pseik raisha but a person doesn’t intend for it? IE, turning on a battery operated light when opening something when the intent is not for the light. If there is an argument, may one rely on the lenient position in a situation of great need? Thank you.
Every psik reisha is when it is aino miskaven, and the fact that the outcome is inevitible makes the aino miskaven into a miskaven. The halachos of psik reisha apply even to things that are only an issur d’rabonon. Maybe you really mean a psik reisha dlo neicha lei, by a d’rabonon. it is controversial if a psik reisha dlo neicha lei needs one or two d’rabonons. There is controversy about this. I can’t give a rule about it and it would have to be dealt with on a case to case basis.
O:CH 320-18, Biur halcha ibid D:H Tov, Shar Hatzion 337-2, Shmiras Shabbos Khilchoso 10 ftnt. 45, Introduction 1 ftnt 41