The Quran, that book that no one reads and that only Islamaphobes think will influence society says quote, "[24:13] Only if they produced four witnesses (you may believe them)."
From [1] Reuters

Pakistan's ruling party has given in to the demands of religious conservatives opposed to the amendment of Islamic laws that would have taken rape out of the sphere of religious law.

A bill to amend the Islamic laws, including the one that requires rape victims to produce four male witnesses or risk an adultery charge, has been fiercely opposed by the conservatives.

I can imagine very few situations where four non-particpating men witness a rape. But maybe I am just not big enough mentally.