As other evidence established that the date of delivery of the second accused’s car was 14 December 1988, it follows that if Giaka’s story is true this incident must have occurred on 20 December 1988.
The passage establishes a logical link between the date of delivery of the second accused’s car (14 December 1988) and Giaka's story, suggesting that if her account is true, the incident must have occurred on 20 December 1988.