The regulators address this in the 2005 ODP guidance document:
Equal Credit Opportunity Act
Under the Equal Credit Opportunity Act (ECOA) and Regulation B, creditors are prohibited from discriminating against an applicant on a prohibited basis in any aspect of a credit transaction. This prohibition applies to overdraft protection programs. Thus, steering or targeting certain consumers on a prohibited basis for overdraft protection programs while offering other consumers overdraft lines of credit or other more favorable credit products or overdraft services, will raise concerns under the ECOA.
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