Miller was one of six state attorneys general, all of whom belonged to the Democratic Party, who received the highest rating, a letter grade of A+, from the June 2008 Survey and Scorecard report published by the political organization, ACORN. The report was published in an effort to shine the spotlight on state attorneys general "leading the fight to protect homeowners from joining the flood of Americans losing their homes to foreclosure," according to the group.

Miller led the roughly three year-long multi-state negotiations in the effort to settle with several U.S. banks over alleged abuses and faulty documentation used in the seizure of homes since the crisis began in 2008. The deal, which 49 states ultimately agreed upon in February 2012 (Oklahoma's Scott Pruitt made an independent deal for his state), was expected to give up to $40 billion to struggling homeowners, and an estimated "1 million U.S. homeowners who were "underwater" on their mortgages -- with principal exceeding the home's value -- were eligible for as much as $20,000 in relief of principal owed." Attorneys general from numerous states collaborated on the deal to provide immediate assistance to their states' constituents, with notable exceptions, including California's Kamala D. Harris (D), New York's Eric Schneiderman (D) and Delaware's Beau Biden (D). Campaign finance investigation According to the National Institute on Money in State Politics, which investigated the foreclosure practices of prominent banks, Miller accepted significant contributions to his 2010 re-election campaign from out-of-state lawyers. Without making any specific allegations, NIMISP suggested the timing and scale of Miller's contributions from out-of-state and legal sources was related to his investigation. NIMISP noted that Miller's 2010 contributions from out-of-state sources and from lawyers and lobbyists in general greatly exceeded what he had previously brought in from those demographics. Although Miller raised twice as much in 2010 as he had in his 2006 and 2002 campaigns combined, he raised more than ten times as much from lawyers and lobbyists in the finance, insurance and real estate sectors. In particular, $170,300 -- over 20 percent of Miller's total contributions -- came between September 30 and election day, after Miller announced the beginning of his investigation on October 13. Although it is not unusual for a large proportion of candidates' contributions to come in the last month before an election, the NIMISP report argued that the discrepancy between Miller's out-of-state contributions from lawyers and lobbyists in 2010 and in previous campaigns suggested a link with his investigation.