Welcome to ATS' own wiki.
Read and remember the rules and conventions, they can be found at Help
The name "Tricameron" refers to the three-chambered nature of the Romulan government.
The upper chamber is the Fvillhaih, or Praetorate. There are two evenly-ranked lower chambers, collectively called the Deihuit, or Senate. Of the two houses of the Deihuit, one has the function of creating and passing laws, the other has the single function of vetoing unsuitable laws passed in the other house of the Deihuit. Following the passage through the vetoing house, the law goes to the Fvillhaih for final approval.
The RSE has no single head of state.