Generally speaking, yes--the heirs should be able to ask for any accounting documents. Unfortunately, however, I cannot tell why "they did not appreciate even an implication of" you asking for such documentation.
I agree with attorney Berjis. If you are the heir pursuing the wrongful death case, you should have access to accounting documents relative to settlement. If the action is ongoing, however, the accounting may not be complete which may explain their hesitation.
You can ask for an accounting as to YOUR settlement or award. Asking for information about others depends on the circumstances and whether there are overlapping, and possibly competing or conflicting interests, in which case you may be better off hiring or consulting independent counsel.
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