Patient-doctor confidentiality is practically inviolate. Even the most avid of paparazzi had to rely on Britney's parents, not her physician, for the scoop on the pop star's current health. But Blue Cross, according to today's L.A. Times, apparently has no problem tipping over that sacred cow:

The state's largest for-profit health insurer is asking California physicians to look for conditions it can use to cancel their new patients' medical coverage.

Blue Cross of California is sending physicians copies of health insurance applications filled out by new patients, along with a letter advising them that the company has a right to drop members who fail to disclose "material medical history," including "pre-existing pregnancies."

Doctors are supposed to treat people, not serve as insurance companies' watchdogs for the bottom line. So here's what I don't understand: How exactly did Blue Cross of California think that this letter — which basically asks doctors to snitch on new patients — would play in the media?

It certainly didn't play well with doctors:

"We're outraged that they are asking doctors to violate the sacred trust of patients to rat them out for medical information that patients would expect their doctors to handle with the utmost secrecy and confidentiality," said Dr. Richard Frankenstein, president of the California Medical Assn.

Patients "will stop telling their doctors anything they think might be a problem for their insurance and they don't think matters for their current health situation," he said.

Insurance industry representatives claim that sending these letters out isn't a new practice, although prominent doctors told The Times they'd never seen anything like it. And given the controversy surrounding the practice, I can see Blue Cross arguing that this is one way of keeping the decisionmaking process up-front.

Maybe so. But there's probably a more practical reason that this letter is coming into sharp focus now. Sicko, Michael Moore's 2007 documentary on the evils of the healthcare industry, explored one particular corporate sin in detail — the practice of rescission, or cancelling coverage after treatment has been approved. This would happen once healthcare costs had skyrocketed — a company would go back and find some minor discrepancy or forgotten illness buried in patients' medical records, and use that as a justification to abandon them.

And according to American Medical News, the courts recently declared certain types of rescission illegal:

The 4th District Court of Appeal unanimously said insurers have a responsibility to make sure patients' policy applications are complete and accurate before issuing coverage — not after expensive claims come in the door. Judges said plans cannot revoke patients' policies unless they fully investigate pre-enrollment forms up front or insurers show patients intentionally misled them.

When the courts say you can't pull the medical rug out from beneath patients, what's a down-and-out insurance company to do?

Ask the doctors for help, apparently.