Answer:
One Roman emperor who was known for his cruelty and for killing many innocent people without fair trials was Emperor Nero. Nero was accused of killing for his own enjoyment, and he was known for his brutal treatment of those who opposed him or who he saw as threats to his rule. He is also infamous for being one of the few Roman emperors to be declared a public enemy by the Roman Senate, and for being the first Roman emperor to be assassinated.