Since 1954, players have had to wait five years after retirement to become eligible for Cooperstown through the Baseball Writers' Association of America. It’s generally a good rule, allowing emotions to cool and Hall of Fame voters to gather perspective on a player’s career before making their decision.
In a few instances, the writers have waived the five-year rule. Roberto Clemente drew 393 of a possible 424 votes in a special election in March 1973, months after his death flying relief supplies to victims of a Nicaragua earthquake. Darryl Kile, Rod Beck and Cory Lidle have all also appeared on Hall of Fame ballots sooner than five years after their untimely deaths, a show of respect mostly for players who otherwise wouldn’t have approached Cooperstown.