Updated: 18-aug-2006


Our web-based Group Unity Scores (GUS) utility produces a score that shows to what extent a member of Congress voted "with" or "against" a group of other members.

For example, if the "group" represents the leadership of one political party, the score for a particular member indicates whether the member voted "with" or "against" the party. These scores are sometimes referred to as party unity scores.

The score is a number between 0 and 100 where 100 indicates that a  member voted "with" the group on all analyzed votes. Votes Breakdown reports show roll call numbers of the votes during which the target member voted "with" and "against" the group. A list of "ignored" votes (the ones excluded from the GUS score calculation) is also available.

The GUS utility requires that JavaScript and cookies be supported AND turned on in your browser. Please see our Privacy Policy for more information. Also note the utility "times out" if not used for 20 minutes.

Here are the main steps needed to generate a Group Unity Score for a member:

Whenever the utility displays information about a member of Congress, 'C' indicates a 'currently serving' member and '? ' indicates that the date of the beginning of the member's term in office is unavailable.


Vote - a recorded (Roll Call) vote taken by one chamber of Congress.

Target Year - the year during which the votes analyzed by the GUS utility were taken.

Target Chamber - the chamber (House or Senate) where the analyzed votes were taken during the target year.

Target Member - a member of the target chamber for whom the GUS score is to be calculated by comparing his/her voting record in the target year with that of the reference group.

Reference Group - a user-defined group (between 1 and 10 members) of the target chamber.

GUS Algorithm Details

The utility requires the following user input:

First, the utility creates a list of all votes the target member voted Yea, Nay, Paired For, or Paired Against during the target year. Then it eliminates any vote for which 

For each of the remaining votes, the position (FOR or AGAINST) of the reference group on the vote is determined using the following rules:

Finally, the group unity score is calculated for the target member as a percentage of all votes still under consideration during which the member voted (or paired) in agreement with the position of the group as determined above.

Roll Call numbers of the votes during which the target member voted "with" and "against" the reference group and the votes "ignored" (excluded from the GUS analysis) are available by clicking the corresponding vote counts on the GUS Report page.