Wiktionary says soudcové is an acceptable form: https://en.wiktionary.org/wiki/soudce but it wasn't accepted here.
thanks. I have edited it. Though personally "soudcové" would not pass my lips.
judges are male and female = soudkyne
"Soudkyně jsou užiteční lidé." would be VERY strange. Why only women? And if only women than why lidé and not ženy?
Soudci in general are judges of both/all genders.