An-Nur 24:4

وَٱلَّذِينَ يَرۡمُونَ ٱلۡمُحۡصَنَٰتِ ثُمَّ لَمۡ يَأۡتُواْ بِأَرۡبَعَةِ شُهَدَآءَ فَٱجۡلِدُوهُمۡ ثَمَٰنِينَ جَلۡدَةٗ وَلَا تَقۡبَلُواْ لَهُمۡ شَهَٰدَةً أَبَدٗاۚ وَأُوْلَـٰٓئِكَ هُمُ ٱلۡفَٰسِقُونَ 4

And those who accuse chaste women and then do not produce four witnesses - lash them with eighty lashes and do not accept from them testimony ever after. And those are the defiantly disobedient