question: What may be invalidated if there was an erroneous understanding of a fact or situation at the time of conclusion of a treaty ?
answer: A state 's consent
turker_answer: A state 's consent may be invalidated if there was an erroneous understanding of a fact or situation at the time of conclusion of a treaty .
rule-based: A state 's consent may be invalidated if there was an erroneous understanding of a fact or situation at the time of conclusion of a treaty .