Yevamos 54a - Giving up your life and Capital punishment

Sometimes when you are physically forced to do an issur, you are not doing the issur at all. For example if someone bends your body in front of avodah zarah, you are not doing the issur at all. Similarly, R' Chaim points out that if you are being forced to allow yourself to be thrown on a child, you are not doing the issur of retzicha at all. However, sometimes when you are forced, you are still doing the issur. For example if someone puts non-kosher food down your throat, you did the issur of eating issur just that you were physically forced (which is: 1. o'nes 2. passive). Similarly, if you are physically forced to commit adultery, you did the issur just that you were physically forced (R' Chaim asks how tosafos can compare a passive act of adultery to a passive act of murder since by adultery you committed the issur, but by murder you were just a weapon. see R' Elchonon 48 who explains Tosafos).

Tosafos assumes that the rules for yehareg v'al ya'avor are that if you are being forced to do an issur actively or passively doing an issur b'ratzon (willfully), you must give up your life. But if you are: 1. being forced to violate the issur and 2. passive i.e. karka olam, you do not have to give up your life. However, the rules for when you are liable for capital punishment is different. Originally (when Tosafos asks the question from yehareg v'al ya'avor) Tosafos holds that whenever you were supposed to give up you life and instead violated the issur, you are liable for capital punishment. But, Tosafos then changes that whenever you are forced, you are not liable for capital punishment. But if it was intentional you are liable for capital punishment, regardless of whether you were active or passive.

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