Public policy it set, to a large degree, in democracies by elected officials or officials appointed by elected officials. Thus the groups most likely to influence the policies of those officials are those groups most likely to vote. The percentage of people in a given age cohort that votes increases dramatically with age. In 2010, less than 21 percent of eligible 18- to 21-year-olds votes, while over 61 percent of people over the age of 65 voted. That means that because the young have less effect on the outcome of elections, their opinions are of less interest to officials standing for elections than those of people more actively involved in the democratic process.
The wealthy are also important to those who set public policy due to their ability to contribute to campaigns and the power that wealth brings. Similarly, opinion leaders can influence policy directly by have the ear of those who set policy. The well educated are also more likely to vote than the less educated, and more likely to themselves become either elected officials or riser to important positions in the civil service. They are also capable of articulating their interests in a more convincing manner and having the knowledge and connections to apply pressure to elected officials than less well educated people.