Machine learning is being integrated into a growing number of critical
systems with far-reaching impacts on society. Unexpected behaviour and unfair
decision processes are coming under increasing scrutiny due to this widespread
use and its theoretical considerations. Individuals, as well as organisations,
notice, test, and criticize unfair results to hold model designers and
deployers accountable. We offer a framework that assists these groups in
mitigating unfair representations stemming from the training datasets. Our
framework relies on two inter-operating adversaries to improve fairness. First,
a model is trained with the goal of preventing the guessing of protected
attributes' values while limiting utility losses. This first step optimizes the
model's parameters for fairness. Second, the framework leverages evasion
attacks from adversarial machine learning to generate new examples that will be
misclassified. These new examples are then used to retrain and improve the
model in the first step. These two steps are iteratively applied until a
significant improvement in fairness is obtained. We evaluated our framework on
well-studied datasets in the fairness literature -- including COMPAS -- where
it can surpass other approaches concerning demographic parity, equality of
opportunity and also the model's utility. We also illustrate our findings on
the subtle difficulties when mitigating unfairness and highlight how our
framework can assist model designers.Comment: 15 pages, 3 figures, 1 tabl