All we have is a few unanswered questions and circumstantial evidence.
There was thus very strong circumstantial evidence in favour of fertilization, although the male nucleus was not traced.
Teeth of the carnivorous dinosaur scattered among the bones of the herbivorous dinosaur completed the line of circumstantial evidence.
The most incredible tales talk of wealth and power to clothe the lives of the historical heroes of the past.
His famous description of Greek fire has a most provoking mixture of circumstantial detail with absence of verifying particulars.
Strangely enough, however, the government passed over the incriminating conversation with Greenway, and relied entirely on the strong circumstantial evidence to support the charge of high treason against the prisoner.
I can't say that for sure, but only because there's no direct proof—only circumstantial evidence.