How did the common people gain influence in the roman republic?

In 509 B.C.E. the Romans conquered and overthrew Etruscan conquerors who had ruled over them for hundreds of years. After that, the Romans established a republic government where the citizens elected their representatives to rule on their behalf.

With this republic government, the citizens gained many rights like the they could vote, marry, practice business and many other rights. Though the citizenship varied greatly and was divided into many types but overall the citizens had many rights and thus the common people had gained influence in the Roman republic.

so they can defeat there oppenent

it is the code of hammurabi