Burton Kaplan
PER
Kaplan Burton Kaplan
Mr. Casso attributed that last crime to Burton Kaplan in a move that indicates how confounding the federal trial has been, his former partner in crime, who has since become a government witness in the case. For the next 12 years or so, prosecutors chipped away at Mr. Kaplan to get him to cooperate, and last year they won his help. In the first week of the trial, acting as a substitute for Mr. Casso, Mr. Kaplan told the jury that he had served as ''the safety spot,'' or liaison, between his former mob associate and the two retired detectives, who are accused of eight murders.