Political parties and political interest groups are both intermediaries through which people can make their views known to government and through which they can try to influence public policy. In my view, political parties have a greater influence on government policy than interest groups, because they are a long-term, consistent influence heavily embedded within the political system – in terms of both elected members and voter support.
Political parties and political interest groups are both vehicles for political change. However, political parties are formal organisations, i.e. normally registered with the FEC. These organisations intent to change government policy from within established institutions through members holding elected offices in government. Political interest groups can be any type of organisation or group united by a common political goal, that attempts to influence those in elected office to support their cause. These interest groups usually focus on a narrow set of policy goals; political parties unite interests over a way broader base. Based on these definitions, I argue that political parties have a greater influence on government policy, because they deal with government directly through their members, instead of indirectly through lobbying efforts; and they deal with policy comprehensively, instead of focusing on a narrow set of policy issues. Arguably, the latter argument suggests an interest group may have more influence than a political party concerning specific issues, because they can leverage information about this issue that the party does not have access too, or may not care about. However, in these cases the final decision will still be made by someone operating from within established institutions rather than by someone outside of them.
However, these definitions of political parties and interest groups are rather narrow and therefore limited in their explanation. In the end, which has more influence may depend on how individual political parties and interest groups are organised: highly organised interest groups (e.g. the tea party, as mentioned in Dr. Patterson’s lecture on interest groups) may have more influence than poorly organised political parties with no seats in government (e.g. the green party), and the reverse is true as well: highly organised political parties (e.g. the democratic and republican parties) may have more influence than poorly organised interest groups (e.g. Occupy Wall Street, as mentioned in Dr. Patterson’s lecture on interest groups).
So, when the question is interpreted as whether a political party or interest group has more influence, when both are equally well organised, I argue – as I did above – that political parties tend to have more influence on government policy than interest groups, because they are a more consistent force. Nevertheless, it is important to note that this cannot a priori be assumed for any case, because influence is contingent on institutionalisation, sustainability, and legitimacy.
* For EdX course “American Government”, courtesy of Harvard University.