Ideological constraint exists when a general principle helps a person reason across policy domains, so that one position makes other positions more predictable. Many citizens show partial rather than complete constraint because they balance several values or pay close attention only to selected issues.

Measure self-identification, party attachment, concrete issue positions, and the reasoning behind them separately. A familiar label is evidence about identity; a recurring principle across multiple issues is stronger evidence of ideological organization.

Consider a citizen who objects to government coercion in business licensing, police searches, and limits on unpopular speech. Those answers do not fit neatly into every current coalition, but they are connected by a recognizable principle. Another citizen may call herself conservative because that is her family's political identity while supporting policies associated with several ideological camps. The first pattern may show more constraint even though the second person uses the clearer label.

Video lesson: Public Opinion: Crash Course Government and Politics #33