What I actually want to know is if you had the same number of other average cars driving the same distance as the Teslas, how many people could you expect to be killed in these cars.

Here is my crude estimation. If we consider that there are 3.2 * 10^-4 people killed in traffic per car per year[1] and that there are 20000 Tesla Model S on the road[2], then we get that there should have been about 6 deaths.

Now most of the Teslas have not been on the road for a whole year probably so I'm not sure how valid this estimation is.

This seems to be some indication that zero deaths is very low for this number of cars but to be sure I think one would need to make a more detailed estimate. Doing some statistical analysis would also be good.

[1] https://www.wolframalpha.com/input/?i=traffic+deaths+per+car... [2]http://en.wikipedia.org/wiki/Tesla_Model_S