What is “disparate-impact” discrimination under Title VII and how does it differ from “disparate-treatment” discrimination?

1.  What is “disparate-impact” discrimination under Title VII and how does it differ from “disparate-treatment” discrimination?

2.  Do you believe that an employer that refuses to hire felons – regardless of the nature of the felony, the nature of the job, or the length of time that has passed since the conviction – should be subject to liability for disparate-impact discrimination?  What defenses might an employer use to defend itself against a lawsuit challenging the legality of its policy against hiring felons?