The article addresses 8 ways that employers can legally discriminate; this one is in regard to unemployed job seekers:
Discrimination against the unemployed is indeed legal. Many companies consider unemployment to be a factor that automatically disqualifies applicants. Unemployment discrimination is rampant. While a handful of states (New Jersey, Oregon, D.C.) have passed laws against unemployment discrimination, it's legal almost everywhere in the United States. Other states have tried to pass laws and failed or been vetoed. President Obama has proposed the American Jobs Act, which has many provisions that will help put Americans back to work. Included in that law is a prohibition against discriminating against the unemployed, but it hasn't passed yet. Unemployment is having a disparate impact on older workers and minorities, so you might be able to pursue a discrimination claim if you've been subjected to unemployment discrimination and a less qualified younger employee or person of a different race, sex or national origin was hired.
The full article: