Key policy decisions are made by the leadership in some legislatures, by a policy committee in other bodies, and by majority party caucus in yet others. Every legislative body has its own distinct quirks and folkways. Laws are grown in the sunshine. With few exceptions, the legislative process is a very open one. There is ample opportunity at various stages for participation by every citizen who has inputs and opinions to express.
Legislatures are fiercely political places.
Almost all legislators are nominated through partisan political processes and chosen in partisan elections. The political party that wins a majority of the seats in each legislative body also wins the right to pick the officers of that house, the committee chairmen, and often the staff. Although political parties are not as powerful in elections as they once were, they still are very potent forces in determining the organization of the vast majority of legislatures. In some states, legislative party caucuses have enormous power and individual lawmakers vote against their decisions at great peril. Every significant bill and issue is weighed, not only on its merits, but also on political considerations.