Bulugh al-Maram, Book 10, Hadith 1260 (English)

Al-Baihaqi transmitted on the authority of 'Ali (RAA) that he said, 'Avert the prescribed punishment by rejecting doubtful evidence.'

وَرَوَاهُ اَلْبَيْهَقِيُّ: عَنْ عَلِيٍّ ‏- رضى الله عنه ‏- (مِنْ)‏ قَوْلِهِ بِلَفْظِ: { ادْرَأُوا اَلْحُدُودَ بِالشُّبُهَاتِ } (1588)‏ ‏5 ‏- ضعيف جدا أيضا.‏ رواه البيهقي (838)‏.‏

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also referenced under: Book 10, Hadith 1221 (In-Book)