Defense lawyers for a Canadian executive sentenced to 15 years prison in Cuba on bribery and other charges released a raft of documents on Sunday seeking to bolster their case that Cy Tokmakjian was denied a fair trial. Tokmakjian’s transportation company said crucial evidence prepared by the defense team was not accepted by the five-judge panel during the two-week trial in June, and relevant witnesses including experts were denied a chance to testify.