Cobb cites a 2014 report by Emory law professors Joanna Shepherd and Michael S. Kang that found a strong link between campaign spending and ruling against criminal defendants: Skewed Justice: Citizens United, Television Advertising and State Supreme Court Justices' Decisions in Criminal Cases.
Cobb is one of four former chief justices of Texas and Alabama who submitted an amicus brief urging the Supreme Court to uphold Florida's rule that bans direct solicitation by judicial candidates. The case is Williams-Yulee v. Florida Bar (docket number 13-1499), which was argued in January. On the other side, the ACLU has an amicus brief arguing that the ban infringes free speech. For much more about the case and the arguments, see SCOTUSblog.