Others contest these conclusions, stating that family courts are biased in favor of fathers and that the lower percentage of separated fathers as custodial parents is a result of choices made by fathers rather than bias of family courts. According to sociologist Michael Flood, father's rights activists have exaggerated the disparity in custody awards between mothers and fathers, and ignored the fact that in the vast majority of cases, fathers voluntarily relinquish custody of their children through private arrangements; either because they are willing to do so, or because they do not expect a favorable court ruling.