Well it seems there's no source yet, I'll look into it if I get bored. I've long believed there was discrimination in the situation though and I suppose I'll tell you why so we can drop the thief claim excuse for it.
This was back in the 90's. Friend of mine was 8 months pregnant with her first child, her husband was the general manager of a local construction company and they were easily upper middle class. She had quit her job to stay home with baby (they were kinda old fashioned.) Her husband hit a moose on the highway and didn't pull through his injuries. They didn't have life insurance on him and she had to use most of their meager savings on COBRA for pre natal care (she was anemic) and the birth of course. She ended up in the hospital for the last couple weeks of the pregnancy because her son had turned and there was concern the umbilical cord was going to strangle him.
Anyway, after her son was born she was stuck in the single parent problem - how can you go to work when it costs so much to pay for day care? At minimum wage it's about impossible: daycare's $10-$15/h or more where I am right now. -- Anyway, so I tell her to go down to the welfare office for help. Cause us stupid white middle class folks actually think that's what it's for, helping people in a rough patch. - She told me that the case worker said her husband had made too much money that year, unless she was a minority... Well she happened to have a little native in her, third cousin once removed kind of shit.
So yea. Explain that one away.