Answer:
I think Tybalt is the cause of the chaos, due to every time he comes around in the play, there is violence that ensues. He tried to get Lord Capulet to bring harm to Romeo at the Party, and ended up getting kicked out himself, he fought Benvolio in the beginning, when he tried to play peacemaker. Tybalt is definitely a loose cannon in the play, and seems to act before thinking.
Step-by-step explanation:
Benvolio urges Mercutio to come away with him and avoid the Capulets in the streets. Mercutio brushes him off. Tybalt and other Capulets arrive, whom Mercutio taunts. Benvolio tries to move the conflict somewhere private, but Romeo interrupts with his arrival. Tybalt challenges him to fight, citing prior grievances; Romeo refuses and attempts to de-escalate the situation. Mercutio goads Tybalt into a duel, which Romeo tries and fails to stop. Tybalt stabs Mercutio, who in his dying moments curses both the Montague and Capulet houses. Benvolio informs Romeo that Mercutio is dead; upon re-encountering Tybalt, Romeo fights and kills him. Benvolio convinces Romeo to flee before passersby arrive. The Prince and both families then arrive to the scene. Benvolio explains what happened, but Lady Capulet, observing Benvolio to be biased, urges the Prince to punish the Montague family by executing Romeo. The Prince chooses instead to banish Romeo from the city.
MONTAGUE
Not Romeo, Prince. He was Mercutio’s friend.
His fault concludes that which the law should end:
The life of Tybalt.
PRINCE
And for that offense
Immediately we do exile him hence.
I have an interest in your hearts’ proceeding—-
My blood for your rude brawls doth lie a-bleeding.
But I’ll amerce° you with so strong a fine
That you shall all repent the loss of mine.
I will be deaf to pleading and excuses.
No tears, no prayers, shall bribe away abuses.
Therefore use none. Let Romeo hence in haste;
Else, when he is found, that hour is his last.
Bear hence this body and obey our will.
Mercy but murders, pardoning those that kill.