I especially appreciated the well-researched comparisons between the Vinayas/Vibhangas of different Theravada traditions:
There are several Vinayas in existence, each of which can trace its origins back to the time of the Buddha. They share a core of rules and procedures, but the explanations and stories differ somewhat, as they were settled and organized in the few centuries following the Buddha’s life. Each represents a historical school of Buddhism in India, only three of which survive and are practiced today: the Theravada Vinaya in Pali, the Dharmaguptaka Vinaya in Chinese translation, and the Mulasarvastivada Vinaya in Tibetan translation.
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the Vinaya in general holds a very high standard of presumption of innocence. Typically, a monk or nun cannot be held guilty until they have actually confessed.
The Aniyata rules appear to present an exception to this. This creates a tension between the presumption of innocence and the emphasis on believing the woman’s testimony. As we have seen, contemporary studies show that a woman’s testimony is reliable, thus supporting the exceptional case of the Aniyata rules. It should be noted that the Pali Vibhanga, the old commentary on the rules, undoes this, requiring that the monk confess. However, if we compare Vinaya texts of different schools, we find that most of them—namely, the Mahasanghika, Mulasarvastivada, Sarvastivada, and Dharmaguptaka—allow legal action to be taken solely on the basis of the woman’s accusation, although each works out the exact details somewhat differently. In this case, the Pali Vibhanga is clearly the exception, and does not represent the consensus of the ancient Indian sangha.
In addition, in the Pali Vibhanga, the slightest flaw in the woman’s testimony is sufficient to dismiss the whole case. For example, if she says, “I saw you sitting down having sex with a woman,” and he says, “I wasn’t sitting but lying down,” then he gets away with it.
The rule laid down by the Buddha emphasizes believing women and holding men accountable. The Vibhangas, written some centuries later—with the notable exception of the Dharmaguptaka—shift the focus to exonerating men and disbelieving women.
The medieval Pali commentary Samantapasadika, by Acariya Buddhaghosa, justifies this by pointing out that sometimes what is seen is not what really happened. He is not suggesting that the woman is lying, merely that she may be mistaken.
However, the Thai commentary Vinayamukha, by Sangharaja Vajirananavarorasa, points out the fallacy in this idea. If in the end only the bhikkhu’s word is accepted, then the “trustworthiness” of the laywoman becomes meaningless. To be trustworthy is more than just not lying—it is to be a reliable source of information. Someone who is trustworthy can, by definition, be trusted to know what it is that they saw and describe it properly. This argument is substantially the same as the position of the Dharmaguptaka Vibhanga. Vajirananavarorasa concludes that “trustworthy” indicates that the authorities should believe in her testimony.
He also accepts the implication of this, namely that the testimony of the laywoman can be sufficient even if the bhikkhu denies the charge. He further agrees that by restricting “trustworthy” to only “noble disciples,” the Vibhanga is “defining it on an excessively high level.” He assigns this definition to the “arranger” of the Vibhanga rather than to the Buddha.
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These reasonable considerations by the Thai Sangharaja were walked back by the American commentator Thanissaro Bhikkhu, who discusses this point in his Buddhist Monastic Code, an unofficial manual for Vinaya practice among contemporary Western monks. He acknowledges that “the Buddha at one point was willing to let the bhikkhus give more weight to the word of a female lay follower than to that of the accused bhikkhu.”
Yet the burden of his analysis is given over to explaining at length how a monk can only be held accountable if he confesses. While admitting that the texts on which he relies are later, he argues that they “supersede” the earlier rule, which was laid down by the Buddha. Thus the exoneration of the patriarchs takes precedence not only over the woman but over the Buddha himself, and even over the Thai Sangharaja, the former head of the lineage to which Thanissaro owes allegiance.
Thanissaro makes the extraordinary argument, used nowhere else in his manual, that even if guilty monks get away with it, in the long run their karma will catch up with them—small comfort to the women. But then, the welfare of women is never a factor in these debates, and a woman’s perspective is never invited.