An apparent Islamic State document captured by U.S. Special Operations Forces and released by Reuters this week lays out guidelines for sexual relations between enslaved women and members of the extremist group. The fatwa ruling (which you can read in a U.S. government translation) is the latest glimpse into an entrenched and well-documented system of sexual abuse honored by the group.

According to Reuters, the fatwa was a part of a larger trove of documents taken by special forces during a targeted raid in May. It was not independently verified by the news outlet.

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The document details rules for "owners" of women captured by the militant group on having sex with their captives. Among other things, the guidelines instruct slave owners to not to have sex with female captives until after their menstrual cycle, not to have sex with them if they are pregnant, and, in the case of two sisters being owned by the same person, to have sex with just one, not both, unless one is given away or released.

Reuters - thomsonreuters.com

The fatwa was issued by the militant group's "Committee of Research and Fatwas" in response to an apparent question about the treatment of female slaves:

Some of the brothers have committed violations in the matter of the treatment of female slaves. These violations are not permitted by Sharia law, because the rules have not been dealt with in ages. Are there any warnings pertaining to this matter? May Allah protect you.

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Reuters notes that the injunctions don't necessarily mean that the detailed activities were taking place, just that members were warned against them. Still, some of the rules are specific, such as one detailing sexual relations with a mother-daughter captive.

If the owner of a female captive, who has a daughter suitable for intercourse, has sexual relations with the latter, he is not permitted to have intercourse with her mother and she is permanently off limits to him. Should he have intercourse with her mother then he is not permitted to have intercourse with her daughter and she is to be off limits to him.

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The Islamic State's sexual mistreatment of women and girls — especially those belonging to the Yazidi religious minority — was documented extensively this year by human rights groups and journalists. An August report in The New York Times explained how the group "codifies sex slavery in conquered regions of Iraq and Syria and uses the practice as a recruiting tool," and a Human Rights Watch report in April examined the "organized and methodical" way captive women and girls were set up to be distributed among Islamic State members.

The fatwa also includes an instruction to "show compassion" toward female captives, to "not humiliate her, and not assign her work she is unable to perform." Islamic scholars have widely decried the Islamic State's use of slavery, saying the practice is forbidden by Islam.