Feasibility of "murder" in relation to sibling rivalry for the mother's one-sixth share

Despite the consensus of the Imami and Sunni jurists about the principle of the exclusion of brothers for the mother and, as a result, her deprivation of the surplus share of the mother's one-sixth (share), the difference of opinion still remains that, presuming the brother to be the murderer, whether his right to the surplus share of the mother’s one-sixth (share) is still valid or does committing murder prevent the exclusion of brothers? Induction in jurisprudential sources indicates the existence of different views on this issue, to the extent that the renowned majority of jurists believe that presuming the brother is the murderer, they do not exclude the mother, and some others do not think that murder is an obstacle to the exclusion of brothers; some others have also left the issue in doubt or proposed caution. Conducted with descriptive and analytical method, this research tries to recognize the point of view of non-exclusion of the murderer brothers as a strong and defensible assertion; arguing that the general word “brothers” in verse 11 of Sūrat al-Nisā as a reason for the opposite view can be violable, and on the other hand, documents such as criterion (manāṭ) derived from the narrations about the non-deprivation of infidels and slaves (mamlūk), and inclusion of the mentioned manāṭ in murder - in the manner of refinement of the basis of a ruling and the removal of limitation - as well as the alignment of the consensus or at least the general acceptance of this point of view by the jurists, and most importantly, the allegorical aspect of the above-mentioned topics in the hadiths and non-relevance of the topics mentioned in the successive order of the ruling of non-exclusion, are among the documents that justify the acceptance of the non-exclusion view of the murderer brother. Therefore, the legislator’s approach to follow the unpopular jurisprudential point of view in accepting the assertion of exclusion - in the exception of the third condition of clause (b) contained in article 892 of the Civil Code - is subject to criticism; after proof of claim, removal of the mentioned exception is suggested to the conventional legislator.