If I recall my employment law, it's illegal to use a criteria for hiring that disproportionately affects a protected class (race in this case) unless you can prove that the criteria is inherent to the job. In this case it seems the woman is arguing that the fact that minorities fair much worse with credit histories and have higher conviction rates is race related and that in her case neither of these would prevent her from doing the job. Kind of like saying unless you scored a 1600 on the SAT, you can't work for me but minorities score 1600 at far lower rates than whites and the reason why is do to racial bias. So you have to prove having a 1600 is necessary to do the job or you're discriminating illegally.
I think it's a stretch of an argument. Credit should have nothing to do with it, since she was fired for being convicted of welfare fraud. I think I understand what you're saying, but it seems weird. It's like she can't sue for wrongful termination, even though that should be the crux of the argument: my fraud conviction has nothing to do with bus driving. She's suing because minorities have higher conviction rates? Again, I think I get it...I just don't like it. I don't know all the circumstances, but I wish the employer could have just given her a warning or something or kept close eyes on her or reprimand her for not telling them (if that's what happened). It is messed up that she was already doing the job then got fired. I also wish she sued on different grounds. It's messed up that she's turning a personal responsibility issue (welfare fraud) into a race issue.