A mindguard is one of the postulated positions that exist in the Groupthink theory as identified by Irving Janis.The presence of these mindguards is one of the identified symptoms of Groupthink. This theory postulates that when a group of people, (for instance, a committee) are faced with a decision, the desire for conformity (and therefore the avoidance of conflict) can result in a dysfunctional decision-making strategy such as the making of poor decisions.
The purpose of the mindguard is to "filter" and control the amount of information that is available to the group in the name of attempting to focus, as well as to limit, the number of possible solutions that are likely to arise within the group. This phenomenon can be either positive or negative.
On one side, without mindguards and depending on the situation the number of possible solutions to a given problem could approach infinity. In this case the mindguard phenomenon functions to limit solutions to what is actually viable.
On the other side, the mindguard can limit possible solutions to only that that which creates a bias that is favorable to the committee (and whatever entity they represent). Mindguards are theorized to exist in a variety of group settings but they are not always easy to identify. This adds to the difficulty in countering the phenomenon.
An example of a mindguard is a deadline for a decision. By having a time constraint the possible solutions or decisions are limited to which ones are proposed before the deadline. This can be both positive (the easiest, obvious, or most effective decisions are reached) and negative (superficial solutions, time constraint leads to bad decisions that are rushed).