2021/5781

Application to Self-Driving Cars – Rav Bleich

Now we are finally ready to address the issue of a self-driving car being programmed to kill the one innocent bystander to save the lives of five people it is about to kill. Rav Bleich (in the aforementioned Tradition article) argues that the situations are different. He argues that there is a major difference between being in the situation in which, according to him, the Halachah obligates one to be completely passive and the programmer of a self-driving car programming a situation to preserve more lives.

Rav Bleich believes the programmer to be analogous to the situation described in the following Rama. Rama (Choshen Mishpat 388:2) rules that one may act to prevent inflicting damage upon himself, despite the fact that his deflection of the damage will cause harm to others. For example, if we are forbidden to divert water from our flooded field to another’s field, we may erect a barrier to prevent the water from entering into our field, despite the water entering our neighbor’s field instead.

This Rama is accepted as normative Halachah. The Shach (Choshen Mishpat 163:18) similarly rules that if a government edict was not yet proclaimed against specific individuals, he may take steps to avoid having the edict issued against him, despite the fact that others will be affected thereby. The Shulchan Aruch HaRav (Hilchot Nizkei Mammon 3) also follows this principle, permitting one to take action to avoid soldiers from entering the city in which he resides (to be quartered in its homes) before they enter the city.

The Teshuvot Noda BeYehudah (Yoreh Dei’ah 2:74) clarifies that such preventative action may also be taken by a bystander and not only the person who is trying to avoid the damage to his interests. Thus, Rav Bleich argues while it is not permitted for anyone to divert an arrow already shot to kill someone, one may program in advance of any occurrence to promote the maximum preservation of life. [1] In other words, the programmer’s actions may be defined as a Ma’aseh Hatzalah and not a Ma’aseh Retzichah.

This approach is also adopted by Rav Yosef Sprung and the Rabbis of Institute for Halachic Implications of Emerging Technologies, [2] who authored an article titled, “Halachic, Ethical and Governmental Challenges in the Development of the Autonomous Vehicle.” They explain that when programming the system according to the modus operandi of “saving lives,” we never enter into the question of killing or of judging between individuals, because we never look at actual people. We are only looking at “statistical man” and trying to increase his chances of staying alive – that is, everyone’s chances of staying alive. When the system decides to hit the one and not the many, it is not deciding to kill, it is deciding to save: “Programming the car in a neutral environment [i.e., free of the exigencies of the road] and giving preference to the safety of the many cannot be thought of as a directive to murder but as an expression of the imperative to save lives.” Accordingly, the programming of the autonomous vehicle to save the many fulfills the Chazon Ish’s criteria for framing a case as “saving”: a) the individual is not sacrificed as a means but only incidentally, and b) his death is not considered Hariga BeYadayim.

Application to Self-Driving Cars – Rav Reiss

However, Rav Reiss is not convinced by this argument. First, as noted by the aforementioned Tzitz Eliezer, one may not necessarily be able to extrapolate from a case of damage avoidance to a situation of deciding who will live and who will die.

Moreover, the programmer is analogous to the following hypothetical situation. One sets up a system in advance to handle water entering his field. Thus, if water will eventually enter his field it will be diverted into his neighbor’s field. In other words, he has set up a system that will automatically perform an act he is forbidden to do in such a situation. It would seem logical that it is forbidden to set up such a system even before water floods his field.

Similarly, it should be forbidden for programmers to set up in advance a system for a self driving car to act in a situation in a manner which he would be forbidden to do in that circumstance.

Rav Reiss compares [3] the situation of programming a plane so that if hijacked and flown in the direction of a large building, it will hit a smaller building instead, resulting in fewer deaths. He notes the aforementioned Tosafot that one is not required to forfeit his life to avoid being thrown on a baby and thereby killing it, for who can assume that the baby’s blood is redder than his? So too, argues Rav Reiss, who says that one is obligated to sacrifice his life to avoid other people dying, when he did not create the situation in the first place?

Finally, Rav Reiss notes the aforementioned Kesef Mishneh, that with regard to murder we do not consider the number of people being saved. Thus, he is concerned that programming a car to kill one to save five is classified as programming the car to perform a Ma’aseh Retzichah and not a Ma’aseh Hatzalah.

We may add that it would seem improper to program a car to hit an innocent bystander when the people in danger may be standing in the street illegally. We have mentioned that in such a situation there is undoubtedly no reason for the bystander to have to die due to the reckless behavior of pedestrians who needlessly placed their lives in danger.

Sacrificing One’s Life to Save the Many

Rav Bleich rules that one may not program a self-driving car to drive off a cliff (and thereby kill the driver) to avoid hitting a bus full of passengers head on. In such a case Rabi Akiva’s rule of “Chayecha Kodemim LaChayei Chaveirechah” is in full effect. Moreover, one cannot murder himself in trying to save the lives of others.

However, one could argue that in a case where the driver would anyway have died, there are a formidable group of Posekim who would allow self-sacrifice in such a situation just as Lulinus and Papus - or Roi Klein - were lauded for their saving the Jews of the Lod district through their extraordinary act of self-sacrifice.

Rav Yaakov Medan’s Common Sense Approach

Rav Yaakov Medan is cited by Rav Navon as arguing that one should kill a single person to save five people, based on common sense. The question is whether this is a valid Halachic argument. On the one hand, Sevara is a potent argument. Often the Gemara says, “Lamah Li Kera? Sevara Hu,” which teaches that Sevara enjoys the status of a Din De’Oraita. For example, Bava Kama (46b) states (translation from the William Davidson edition of the Talmud):

Rav Shmuel bar Naḥmani said: From where is it derived that the burden of proof rests upon the claimant? As it is stated in the Torah when Moses appointed Aaron and Hur to judge the people: “Whoever has a cause, let him come near [Yiggash] to them” (Exodus 24:14). This is interpreted to mean that whoever has a claim against another should submit [Yaggish] proof to them. According to this interpretation, this verse demonstrates clearly that the claimant is responsible for supplying the proof. Rav Ashi objects to this: Why do I need a verse to derive this? It is based on logical reasoning that one who suffers from pain goes to the doctor. Just as here the individual with the problem has the responsibility to resolve it, so too, someone with a claim against another must bring a proof to corroborate his claim. Thus, Sevara is a most important source. Indeed, Pnei Yehoshua (Berachot 35a) argues that a Berachah Rishonah constitutes a Torah obligation since the Gemara states, “Sevara Hu Assur Lo Le’Adam SheYehenen Min Ha’Olam HaZeh BeLo Berachah,” “It is logical that it is forbidden for a person to benefit from this world without a blessing.”

However, one could counter that we may use Sevara only when it is rooted in Torah thought or at least in harmony with said thought. In our case, Rav Medan’s Sevara runs counter to the Yerushalmi, which states that we may not give up one person even to save the larger group. Rav Medan responds that the Yerushalmi is not articulating a general rule but applies only to a wartime situation. However, we may respond that the Kesef Mishneh to Hilchot Yesodei HaTorah specifically writes that Sevara does not apply to this issue, and one may simply not kill even just one person even to save a large group of people.

Conclusion

While there are formidable opinions that permit programming a self-driving car to kill one innocent bystander instead of many, the matter is very much still up for debate with regard to a variety of situations. What remains to be seen in the coming years is which side of these debates will emerge as the Halachic consensus among the leading authorities of the generation.

[1] Rav Yehoshua Flug of Yeshiva University (“Pikuach Nefesh Matters Relating to Self- Driving Cars,” Yadrim, Nisan 5777) makes a similar observation: “The Hazon Ish questioned the moral legitimacy of diverting the missile when the individual is actually standing in harm’s way, for this we must say is like “killing with one’s own hands.” However, those who program an autonomous vehicle are only doing so to save the lives of the many and the programming does not take place at the time of the dilemma. Therefore, it seems more reasonable to say that this is not considered “killing with one’s own hands” according to the Hazon Ish.”

[2] This institute is led by Rav Asher Weiss.

[3] Rav Reiss also compares the pedestrian to a baby that has emerged from the mother’s womb. Rambam (Hilchot Rotzei’ach U’Shemirat Nefesh 1:9) writes that we cannot kill the baby to save the mother since “this is the natural course of events, Zeh Tiv’oh Shel Olam”. Similarly, argues Rav Reiss, the pedestrian standing on the street constitutes the normal course of events and we therefore do not sacrifice his life even to save many others.