In Elected Judge May Complete Expert Witness Testimony, Michael S. Frisch, Ethics Counsel Georgetown Law Center writes:
The Florida Judicial Ethics Advisory Committee has a recent opinion on the ethics of a judge testifying as an expert when retained prior to his election as a judge:
ISSUES
May a judge-elect testify as an expert on attorney’s fees at an evidentiary hearing which had commenced while he/she was a candidate for judge but had been continued to conclude his/her cross-examination after the date he/she was elected to the bench?ANSWER: Yes.
More: http://lawprofessors.typepad.com/legal_profession/2012/09/the-florida-judicial-ethics-advisory-committee-has-a-recent-opinion-on-the-ethics-of-a-judge-testidfying-as-an-expert-when-re-1.html