Some of the most energetic characters that sometimes exert a rather heavy influence over the outcome of legislation that emerges are the interest groups. Just like the name states, they are the representatives of a group of citizens that work in a certain domain, which is directly affected by some government decisions. Hence, they try to influence those decisions’ outcome so that they will draw maximum benefit out of it.
Interest groups are varied and their group resources determine their reach. Demographic, economic or political advantages are all at play when the interest groups are set in motion. The greater the leverage, the higher the proposals reach, but sometimes the proposals do not reflect the interests of the group as much as the interests of the group leaders, who actually manage the group resources.
Acknowledging the existence of the interest groups and their involvement in national policy is crucial in understanding why and what is going on on that level. For example, issuing a bill that greatly favors highway building in detriment to the environment may mean that the professional labor and/or the construction interest groups had a heavier say in the matter than their environmentalist counterpart when the matter arose. There’s no rule that states it, but generally groups whose interests contribute to the well being of the economy (jobs, insurance, supplies) usually swing heavier than activists fighting over global warming.