Would you support this exception to the hearsay rule?
When a person makes a statement to another person (witness) concerning upcoming planned terrorist acts, such statements should be deemed to be an exception to the hearsay rule and the witness should be allowed to testify concerning the declarant’s statement.
I must take issue with the above answer as legally insufficient. The obvious exception to the hearsay rule here is that the statement is an admission against interest. If a person tells another that he has committed a criminal act (say homicide) this is an admission against interest; one can be punished for it. The reasoning behind this is that one would not normally make a statement which could be damaging to one unless the statement is true.
In the present instance, terrorist acts are obviously criminal; discussion of planned terrorist acts implies a criminal conspiracy. Either instance involves a situation which is against the speaker's interests, as he is subject to punishment for it. Thus admission against interest is the proper exception to the rule here. The testimony of the conversation is thus admissible.
If I understand what you are asking correctly, I would not support such an exception to the hearsay rule.
My understanding is that you are asking if we would support using a person's statement that he was planning to commit a terrorist act as proof that he did commit the act. If the act has been committed already, I would require that there be actual proof that the defendant committed the act. However, the statement could be acceptable if it were simply being used to prove that the defendant wanted to commit a terrorist act. In such a case, I would be inclined to allow the statement because it would be evidence that would show the state of mind of the defendant.
Just because a person says they are going to do something does not mean that they actually did the thing. This is true for any act, whether it be a terrorist act or not. The fact that a case involves terrorism does not make it any less important to find the truth before deciding whether the defendant is guilty or not. Therefore, I see no reason to accept such a statement as proof that someone actually committed a terrorist act.