Blue Cross Blue Shield of North Carolina is under investigation for possible violations of the law in a letter and robo-call campaign it launched to oppose health care reform.

As Raw Story reported last month, the insurer -- the largest in the North Carolina market -- sent out letters to its customers informing them of an average 11 percent increase in their premiums.

Shortly after, those customers received a mailer from BCBS urging them to write to Sen. Kay Hagan (D-NC) and ask her to oppose health care reform.

That drew outrage from some BCBS customers, who marked up the insurer's postage-paid form letter to Sen. Hagan so that it would read as a letter of support for health care reform (see picture below).

The Institute for Southern Studies reported this week that BCBS's letter campaign, and a follow-up robo-call campaign, are now the focus of North Carolina legislators, 20 of whom wrote to the state's attorney general asking for an investigation.

FacingSouth reports:

20 North Carolina lawmakers -- 19 Democrats and one Republican -- asked the state attorney general and insurance commissioner to examine the mailers and follow-up automated "robo-calls" requesting that Blue Cross customers urge US Sen. Kay Hagan to oppose the creation of a public option to compete with private insurers.

According to the letter ... the lawmakers are concerned that Blue Cross violated the intent of the Do Not Call Registry by using an exemption for a prior business relationship to engage in political advocacy. They also say they believe the company may have violated the law by failing to provide contact information in the phone message.

Nick Pinto and Zachary Roth at TalkingPointsMemo report that the the state's insurance commissioner is looking into the mailing campaign, while the state's attorney general is focusing on the robo-calls.

TPM reports:

Robo-calls are illegal in most situations in North Carolina. Tax-exempt charitable and civic organizations are allowed an exception to this law -- BCBS-NC is organized as a non-profit -- but only if their calls clearly identify the caller, state the nature of the call, and provide contact information. Kirkman noted in the letter that "our initial assessment is that certain calls purported to be made on behalf of BCBS-NC do not appear to meet the third requirement of that exemption provision."

Blue Cross Blue Shield controls 53 percent of the health insurance market in North Carolina, including 98 percent of the state's individual, non-employer-funded policies.