For an audio recording of this shiur, please go to http://www.yutorah.org/lectures/lecture.cfm/785985/_Daniel_Fridman/Rabbinic_Perspectives_on_Gun_Control.
Daniel opened by discussing Asara be-Teves and the different calamities that befell the Jewish people on this day. Then he explained a thematic connection between the Torah portion and the topic of gun control. He noted that in Parashas Vayigash, Jacob could not believe that Joseph was alive until he saw the wagons that were sent to retrieve him and his family. How did this convince Jacob that Joseph was still alive? The midrash teaches that Jacob and Joseph were studying the laws of the eglah arufah (a calf whose neck has been broken) when Joseph disappeared. The eglah arufah is a ritual performed where a body is found outside of a town and the elders of the town perform a sacrifice in which they avow that they were not responsible for the death of the deceased and that they ask God to absolve them of their guilt. This ritual was done over a wadi (stream) and the wadi and the area around could never be used - it had to be a memorial to the dead person who was found. The term eglah (a calf) is similar to the term agalah (a wagon). Hence Jacob saw the wagons as a message from Joseph.
Daniel said that practice of the eglah arufah teaches to take life seriously, and homicide seriously. He said that while the 2nd amendment has different interpretations, for us as religious Jews, we want to know what the rabbinic tradition has to say. For Daniel, this means the sanctity of human life - the fact that man is created in the image of God, that man is a tzelem Elokim - is paramount. He said the the situation with guns now in the country is unacceptable, and he pointed out that in other industrialized countries that do have gun control, the mortality rate from guns is a fraction of what it is here. Finally, as citizens in a democracy, but based on Jewish sources (Talmud Bavli, Shabbat 54b), we have the obligation to speak out and advocate for what is right.
Daniel went on to say that Judaism recognizes the right to self defense, but that this is not an unlimited right.
Daniel brought up the verses in Genesis about Lamech, who was criticized by his wives for teaching his son, Tuval Kayin, how to make copper and iron implements. According to Nachmanides, these are implements of war, and Lamech's response was that while these weapons cause more damage, it is people who kill people, but not the weapons themselves. Of course, according to Jewish tradition, Lamech himself was an inadvertent murderer. He accidentally killed his ancestor, Kayin, and also his son, Tuval Kayin. Since he did not intend to commit murder, he asked that his punishment be delayed for seventy-seven generations.
Daniel then raised the case of the maakeh, the railing that a property owner is obliged to construct on the roof of his building to prevent people from falling off. Based on this idea, as well as the mitzvah of lo ta'amod al dam re'ekha (lit. "Do not stand idly by the blood of your fellow"), Maimonides explains that we are forbidden from creating dangerous situations in which someone become injured or die. Although Daniel did not have a chance to review the Sefer Ha-Chinuch, Mitzvah 546 in the shiur (but on the source sheet), in it the author of the Sefer Ha-Chinuch notes that the Torah commands us to keeps our dwellings and places safe so that no no one will die because of our sins and we will not endangers ourselves and say that we are "relying on a miracle."
Daniel continued to say that the tradition criticizes those who think that weapons are somehow ornaments. Judaism, Daniel observed, is not a pacifist religion, and it understands that war is sometimes justified, but it is far from the ideal. King David, whose war were largely righteous wars, was prohibited from building the Temple because he had blood on his hands. The sages look forward to a messianic time when swords will be beaten into plowshares and spears into pruning hooks (Isaiah 2:4), but one who wears weapons now as an ornament is disgracing himself.
To sum up, we as Jews should promote a society where holiness of human life is championed. Those things which specifically endanger human life need to be removed or fixed so that they are no longer a danger. If we allow a dangerous situation to exist, we transgress the mitzvah of lo ta'amod al dam re'ekha - not standing idly by our neighbor's blood.
If I may add my own two cents, I found Daniel's presentation persuasive. The stand that Daniel proposes should be seriously considered by religious Jews and for that matter by religious Christians as well.
Here are Daniel's sources....