"With regard to speculation:
Personal Knowledge/Speculation (FRE 602)
* Present Sense Impressions: A statement expressing the declarant’s impression of a condition existing at the time the statement was made, such as "it's hot in here", or "we're going really fast". Unlike an excited utterance, it need not be made in response to a startling event. Instead, it is admissible because it is a condition that the witness would likely have been experiencing at the same time as the declarant, and would instantly be able to corroborate.
* Declarations of present state of mind: Much like a present-sense impression describes the outside world, declarant’s statement to the effect of "I am angry!" or "I am Napoleon!" will be admissible to prove that the declarant was indeed angry, or did indeed believe himself to be Napoleon at that time. Used in cases where the declarant mental state is at issue. Present-state-of-mind statements are also used as circumstantial evidence of subsequent acts committed by the declarant, like his saying, "I'm gonna go buy some groceries and get the oil changed in my car on my way home from work."