One of the biggest selling points of Obamacare was that it would finally end discrimination against patients on the basis of pre-existing conditions. But for one vulnerable sector of the population, that discrimination never ended. Insurers are still able to deny coverage to some Americans with pre-existing conditions. And it’s all perfectly legal.

Sixty-five million seniors are in Medicare open enrollment from October 15 until December 7. Nearly 32 million of those patients are enrolled in Medicare Advantage, a set of privately run plans that have come under fire for denying treatment and overbilling the government. Medicare Advantage patients theoretically have the option to return to traditional Medicare. But in 46 states, it is nearly impossible for those people to do so without exposing themselves to great financial risk.

Traditional Medicare has no out-of-pocket cap […]