A "deputy judge" is a temporary judge who helps out when the regular judge cannot be present or when there is a need for an extra judge in a court. They have the same authority as a regular judge and make decisions on legal cases. Full definition
It's not even binding on other deputy judges. (slaw.ca)
Michael Furness QC, sitting as deputy judge of the High Court, decided that this was a case of clerical error, rather than a failure to understand the testator's intentions. (newlawjournal.co.uk)
Michael Furness QC, sitting as deputy judge, held that making a will was not sufficient evidence of severance. (newlawjournal.co.uk)