It is by now well established that Liwa Shuhada' al-Yarmouk (The Yarmouk Martyrs Brigade), a one-time member of the Free Syrian Army Southern Front coalition, has become pro-Islamic State (ISIS) in orientation, using the ISIS flag in its logo and echoing ISIS discourse in its statements.

The brigade has also begun to mimic ISIS's style of administration and governance by controlling a contiguous area of towns and villages in the Yarmouk Valley in south-western Deraa province.

What's not clear is how this transition came about. When exactly did Liwa Shuhada' al-Yarmouk begin leaning towards ISIS? How did it happen? And what is the current state of play in the Yarmouk Valley?

The first claims of a Liwa Shuhada' al-Yarmouk alignment with ISIS came in December 2014 from Jabhat al-Nusra, the al-Qaeda affiliate in Syria, which sparked clashes between the two groups that culminated in a ceasefire brokered by the Salafi rebel group Harakat al-Muthanna al-Islamiya. Though other Southern Front commanders at the time denied that Liwa Shuhada' al-Yarmouk was secretly in league with ISIS, local testimony makes it clear that after the clashes, a connection between Liwa Shuhada' al-Yarmouk and ISIS became a matter of public knowledge in the Yarmouk Valley.

"It began after the clashes. It was in the beginning only that members heard about the DawlaISIS. They liked the manhajideological program, and there was a revolution of the youth, who said: "We want to follow their path if they are truthful,"" Rola al-Baridi, a resident from the town of Jamla, an area controlled by Liwa Shuhada' al-Yarmouk, said via Facebook.

No one, however, was able or willing to confirm the allegations of secret contact prior to that period. As al-Baridi put it, "With regards to whether there was a secret connection with respect to the leadership, this I don't know about. We are speaking about what is in the open."

One member of the group, calling himself Abu Faruk, portrayed his brigade as having always been "Islamic" in orientation. "From the beginning, the brigade was Islamic in formation and thought," he said. This assertion should be taken with a pinch of salt. The term used by locals and members of the group to describe the changes that have come about in the Yarmouk Valley since knowledge of the connection between ISIS and Liwa Shuhada' al-Yarmouk became public is islah, meaning "reform" in Arabic.

Imposing Islamic morality

In this regard, the most notable change has been the establishment in al-Shajra of a separate court as a way to circument the authority of the Dar al-‘Adl, the accepted judicial body among factions in the south. The Dar al-‘Adl considers the court to be illegal. It also accuses Liwa Shuhada' al-Yarmouk of targeting and assassinating members of other factions.

Liwa Shuhada' al-Yarmouk, nevertheless, continued to defy the Dar al-‘Adl, announcing (again) in late July the opening of an "Islamic court," only this time with an "Islamic police" force to accompany it, imitating ISIS' own Islamic police. And in August, Liwa Shuhada' al-Yarmouk set up a Diwan al-Hisba — taking the name ISIS uses for its own department of governance designed to enforce Islamic morality.

Here though, a notable difference exists for now between Liwa Shuhada' al-Yarmouk and ISIS. Both engage in free distribution of the niqab — or face veil — to local women, but so far, wearing it has not become compulsory in Liwa Shuhada' al-Yarmouk territory. "They the Diwan al-Hisba of Liwa Shuhada' al-Yarmouk call on women to wear it and distribute the niqab, but without coercion," says Rola al-Baridi.

The group has also been confiscating cigarettes and closing shops that have been selling them. One member of the brigade, calling himself Abu Layth al-Yarmouki, explained the "reform" as one of gradual implementation, pointing out that the past environment had not made application of Shari'a immediately viable. "Our amir al-Khal the leader of Liwa Shuhada' al-Yarmouk is trying to implement the law of God in this land, but there are obstacles," al-Yarmouki said.

"Besides customs and traditions, there has also been a kafir non-Islamic regime that did not forbid what God forbade: the thief was imprisoned and if he paid a bribe, he got out of his prison," he went on to say. "The man and woman who fornicate, there was no ruling against them. Smoking, drunkenness, prostitution houses, and scandalous dress were considered personal freedom."

A question of motivation

In addition to implementing draconian rulings according to its interpretations of Islamic law, ISIS also places heavy emphasis on the concept of "utopia" (i.e. a life of security and normality) and displaying provision of services in the form of a comprehensive bureaucracy, such as the Diwan al-Khidamat (services department). Though Liwa Shuhada' al-Yarmouk has imitated the utopia concept to an extent, by showcasing the normality of life in the Yarmouk Valley with a photo series of a football match, no evidence exists of services provision from the group. Locals are forced to rely on private generators for electricity and must buy water from individual sellers.

This situation is partly due to the state of siege that exists in the area, as the southern Jaysh al-Fatah (including Jabhat al-Nusra and Ahrar al-Sham) and the Southern Front's al-Farqat al-Awlain in particular try to rout Liwa Shuhada' al-Yarmouk. "There is in our region a committee to distribute bread and humanitarian aid when Jabhat al-‘Ahraderogatory for Jabhat al-Nusra allows it to pass through it to us," said al-Yarmouki. Prices for goods seem high. Al-Yarmouki claimed the price of meat is $6.36 a kilo, petrol is $2.91 a litre, and one roll of bread is $0.07.

Still unclear amid all the details is motivation. What prompted the turn toward ISIS? To be sure, the brigade did not exactly have the best reputation, even as a member of the wider Southern Front coalition. Perhaps the group saw a chance to improve its standing among locals by gradually becoming more Islamic in governance and deepening its affinity with ISIS.

There have been somewhat comparable cases elsewhere in the Syrian civil war: out in the Albukamal area in the east of Deir az-Zor province along the border with Iraq, the local western-backed FSA affiliate Liwa Allahu Akbar, under the leadership of Saddam al-Jamal, clashed with Jabhat al-Nusra in September 2013. Widely viewed as corrupt, al-Jamal later emerged as a defector to ISIS, although allegations of connections with ISIS were not at the center of the initial clashes with Jabhat al-Nusra. One well-connected source in ISIS-held territories said al-Jamal is now the ISIS waliprovincial governor of ISIS' Wilayat al-KheirDeir az-Zor province.

For now, Liwa Shuhada' al-Yarmouk has not become ISIS' Wilayat Deraa in Syria, but that seems to be only a matter of time and partly dependent on whether ISIS can connect the Yarmouk Valley to the rest of its contiguous territorial holdings in Syria. "Inshallah," said one Ahmad Brede of Liwa Shuhada' al-Yarmouk when asked if they would become Wilayat Deraa.

For rebels in the area, destroying Liwa Shuhada' al-Yarmouk is a matter of ever greater urgency, as they may eventually end up trapped in a pincer between ISIS forces to the north and Liwa Shuhada' al-Yarmouk from behind.

Aymenn al-Tamimi is a research fellow at the Middle East Forum, a U.S. think-tank. Focusing primarily on Syria and Iraq. He is currently based along the border with Syria. His website iswww.aymennjawad.org