How does the Roman people's/plebians' inactive participation in government (preferring someone else to make desicions for them) lead to tyranny?in...

Antony offers Caesar the crown three times. The people
shout in agreement. They are giving up their voices to Caesar. According to Casca,
Caesar refused, but each time more gently than the others. Again, the people shout in
agreement that Caesar be
crowned.

CASCA:

...and
he pushed it aside three times, Every time more gently than the last, and at each
pushing aside, My honest neighbors shouted

The people are
shouting for Caesar to be crowned. They are giving up their
voices.

Brutus is worried. He believes that Caesar has become too
ambitious. If Caesar is to be crowned king, that means the people will becomes Caesar's
slaves. Tyranny will be enforced.

The people are
surrendering their voices to the will of Caesar. Caesar will become a dictator. The
people will have no say on any matters of government. When the people give up their
rights, Caesar will take over. Of course, the conspirators will see that this does not
happen.

Brutus does not give up his voice. Brutus maintains
that he loves Rome more than he loves Caesar. For this reason, Caesar must die. Brutus
is an honorable man and he will not sit still and watch Caesar become a tyrant. Caesar
has to die. He has to be stabbed thirty-three times to ensure that Rome will remain free
from tyranny.

Brutus made the mistake in allowing Antony to
live. In the end, Brutus falls on his own sword and Antony becomes one of the most
powerful men in Rome.