Following are a number of back-translations as well as a sample translation for translators of Proverbs 12:17:

• Kupsabiny: “A true witness stands on the truth,
  and/but the one who is a liar, (he) accuses people falsely.” (Source: Kupsabiny Back Translation)
• Newari: “A truthful witness gives true testimony,
  but a false witness tells lies.” (Source: Newari Back Translation)
• Hiligaynon: “A trustworthy witness tells the truth, but the one who can- not -be-trusted lies.” (Source: Hiligaynon Back Translation)
• Kankanaey: “What-is-true is what a trustworthy person testifies, but the not trustworthy, entirely lies is what they tell.” (Source: Kankanaey Back Translation)
• English: “In the courtroom, honest people say what is true,
  but untruthful/dishonest people tell nothing but lies.” (Source: Translation for Translators)