"Nor have I given of it for the dead"Deuteronomy 26:14.

It is forbidden to purchase with Second Tithe funds any item other than food or drink.

The Midrash explains the verse "I have not given of it for the dead" as referring to using the funds to purchase a casket and shrouds. Though such a purchase is a mitzvah, it cannot be done with Second Tithe funds.

It appears to me that purchasing anything other than food items with these monies is like giving the monies to a dead person—who has no gain from such a gift...