From: Rabbi Moshe Sofer
To: Rabbi David
The Chasam Sofer rules that communal taxes and assessments take precedence over a widow's kesubah based on established custom and the principle of tikkun ha'olam, since the wife herself benefits from communal settlement rights and is effectively a co-guarantor of such debts. He distinguishes voluntary charitable pledges, which do not override the kesubah, from mandatory communal levies, which do. Regarding the specific Chevra Kadisha debt, the priority depends on whether the obligation was a general communal levy or a personal membership obligation of the husband alone.
Source: Shu"t Chasam Sofer EH I §142