In act 5 scene 3 of Romeo and Juliet by ShakespeareWho is suspected the most of murder and why?

Until the Friar professes his guilt, Romeo is suspected of murder since his dagger with blood is found near Juliet. However, after the suspects are gathered and each testifies, with the Friar confessing knowledge of all, there are many who are guilty.  For, the true villain in Shakespeare's tragedy, Romeo and Juliet, is the impulsiveness of the characters.

Had Romeo and Juliet not rushed into love, had Romeo not interfered with the quarrel of Mercutio, had Juliet not reacted so hysterically to her father's orders, had the Nurse not foolishly encouraged Juliet to just marry Paris instead of informing her parents, had Friar Laurence not assumed that he could always right things and secretly acted in the marriage and the giving of an elixir to Juliet, had Romeo not assumed that Juliet was dead, and had Friar Laurence not rushed out of the Capulet tomb, assuming Juliet would follow, much of the tragic action could have been averted.  The impulsiveness of these characters makes them all culpable for "the story of more woe of Juliet and her Romeo" (V,iii,309-310).  For this reason, "All are punished"(V,iii,295).