It is disingenous for Kleck to take a quotation of Kellerman’s out of
context to make it appear that Kellermann was asserting that only 2%
of of homicides were lawful defensive homicides.

Dan Day wrote:

Well, your own summary isn’t entirely accurate either. Here’s the
passage in question:

Less than 2 percent of homicides nationally are considered legally
justifiable. [11,13] Although justifiable homicides do not
include homicides committed in self-defense, the combined total
in our study was still less than one fourth the number of criminal
homicides involving a gun kept in the home.

I’ve reread that a number of times and still can’t figure out
exactly what Kellermann is trying to say. The best I can make out
is that Kellermann is claiming that self-defense homicides are not
legally justifiable (?)

You missed the bit where he defined the meaning of those terms:
“Self-protection homicides were considered “justifiable” if they
involved the killing of a felon during the commision of a crime; they
were considered “self-defense” if that was the determination of the
investigating police department anf the King County prosecutor’s
office.[11]” Reference 11 is the FBI definition of “justifiable
homicide”.

Given how Kellermann contrasts “legally justifiable” homicides with
“self-defense” homicides, and the passage as written, the point that
Kellermann underplayed the number of “lawful defensive” homicides
seems a valid one, since it appears he tried to imply that the
defensive homicides which fall outside the 2% “legally justifiable”
category weren’t in fact lawful.

No, he was pointing out that were lawful homicides that fall outside the
2% legally justifiable.