Barbara Pepper (the nosy neighbor) appeared in a total of four Perry Mason (1957) episodes: one in 1957, two in 1961 (including this one), and one in 1963.
One of the few efforts at dark humor in the series occurred when Ida Albright, after viewing her husband's body at the morgue, said that "he wouldn't be caught dead in that" vest.
Although the tattersall vest as shown here is the focus of this episode, the very same vest was worn by various other actors in subsequent episodes.