In his dissent to Caperton v Massey, Chief Justice Roberts warned that the standard the majority opinion articulated as the basis for a required recusal — "probability of bias" — does not provide clear, workable guidance for future cases. He then famously laid out 40 questions raised by the majority opinion, starting with "How much money is too much money? What level of contribution or expenditure gives rise to a 'probability of bias'?" In "Show Me the Money: States, ABA Try to Figure Out When Campaign Cash Leads to a Judge’s Recusal," the ABA Journal tracks states' efforts to answer the questions, and analyzes the further complications posed by Citizens United. Spoiler alert: progress has been slow:
Nearly three years [after Caperton],... fewer than a dozen states have rewritten their recusal rules to account for more common instances of political spending that may not rise to the level of the hard constitutional foul called in Caperton, but that nevertheless create potential conflicts of interest for judges significant enough to warrant disqualification.
Michigan earns a mention in the piece.