Value criterion
In Lincoln-Douglas Debate, the value criterion (criterion, VC, or standard) is the means of weighing the value premise. Unlike the value premise, the value criterion is often swayed to either the affirmative or negative side. It can be shortened to v.c.
Purpose
The value criterion's main purpose is to weigh the value premise, otherwise, the impacts of the arguments in the round are left hanging. An argument in a Lincoln-Douglas Debate generally contains an impact or the effect of that argument (why it matters). This necessitates an objective order to determine which impacts are more important. The value criterion provides this objective order and the round reduces to whichever side achieves the value criterion better. Whether this is done quantifiably or qualitatively is left up to the debaters to decide.
Argumentation
Many times it becomes the vantage point of the debate because the values are, many times, the same in a round. Since each side has impacts that best pertain to their own value criterion, each side must try to convince the judge to weigh the round according to their value criterion.
Example: Resolved: In matters of U. S. immigration policy, restrictions on the rights of non-citizens are consistent with democratic ideals.""
Because "democratic ideals" is what is trying to be achieved in the resolution, most debaters would find it best and effective to use it as a value premise. Therefore, the debate turns to the value criterion. The affirmative, in this case, may use "preservation of procedure" which explains how their value premise is weighed. While the negative may opt to choose "preservation of autonomy". In both instances, both value criteria are attainable by both sides and therefore fair to weigh the round. it would be left up to the debate to determine which value criterion should be used to weigh the round.