Final answer:
The Eighth Amendment protects against excessive fines and cruel and unusual punishment.
Step-by-step explanation:
The constitutional amendment that protects against excessive fines and cruel and unusual punishment is the Eighth Amendment.
The Eighth Amendment states, 'Excessive bail shall not be required, nor excessive fines imposed, nor cruel and unusual punishments inflicted.'
It prohibits the government from imposing punishments that are considered cruel and unusual, and it also limits the amount of fines or bail that can be imposed on individuals.