Who is responsible for the tragic events in Romeo and Juliet?

A number of people are responsible for the tragic events in Romeo and Juliet, including Romeo and Juliet themselves. Since the Montagues and Capulets are feuding families, Romeo and Juliet are fully aware of the social consequences of their actions. Their decision to pursue their love, regardless of the consequences, ultimately results in their deaths. 

Another character responsible for the tragic events is Tybalt. Tybalt becomes enraged when he sees Romeo at the Capulet ball....

A number of people are responsible for the tragic events in Romeo and Juliet, including Romeo and Juliet themselves. Since the Montagues and Capulets are feuding families, Romeo and Juliet are fully aware of the social consequences of their actions. Their decision to pursue their love, regardless of the consequences, ultimately results in their deaths. 

Another character responsible for the tragic events is Tybalt. Tybalt becomes enraged when he sees Romeo at the Capulet ball. The next day, he challenges Romeo to a duel. Romeo refuses, but Mercutio fights in his stead. Tybalt kills Mercutio, and Romeo, enraged at the death of Mercutio, kills Tybalt. This conflict violates the Prince's earlier decree, so Romeo is exiled from Verona.

Another character responsible for the tragic events is Friar Lawrence. Though well-intentioned, the Friar's decision to secretly wed Romeo and Juliet ultimately results in their respective suicides. More specifically, the Friar's decision to give Juliet the sleeping potion eventually results in Romeo mistaking Juliet for dead, and Romeo's grief causes him to commit suicide. Upon waking, Juliet sees Romeo's dead body, so she commits suicide, too.