Mohammed has just left court and proudly displays a document, complete with official seal, attesting to his ownership of a shop in Syria's northern city of Aleppo, a reason to celebrate in the war-torn city, where the rule of law broke down months ago. "It's as if we have a real state," he said, referring to the new machinery of government and justice set up by rebels in those quarters of the city they control. "Now our rights are guaranteed; everything is official." Marriages, inheritances, commercial contracts... they are now all passing through courts manned by lawyers and judges who have abandoned the regime of President Bashar al-Assad and joined the rebellion against it. There are some 20 rebel brigades operating in Aleppo, and the court is run by the most important among them: two jihadist groups -- the al-Qaeda-linked al-Nusra Front and the Salafist Ahrar al-Sham -- and Liwa al-Tawhid, which is linked to the broad-based opposition National Coalition. And while the commanders of these groups are primarily concerned with waging war against Assad's troops, their presence is also felt behind the lines. Liwa al-Tawhid, for example, has created schools and set up an electricity authority in an attempt to resupply neighbourhoods deprived of power over nine months of fierce fighting. "The idea," one rebel commander said, "is that there won't be a single day of vacuum when the regime falls; the administration and (public) institutions must be operational from day one." But for now, there are more pressing issues affecting the populace in a city struggling to maintain some semblance of public order -- theft and looting. Whether it be ill-disciplined fighters from the rebel Free Syrian Army, or merely common criminals posing as members of the FSA, people are worried about their property. "Men claiming to be FSA come to steal our things," bemoans Umm Ahmed. And after bombings, "you occasionally see them rooting through the rubble." And because theft and robberies have been on the rise, Abdullah has come to court. "I want to move house, so I have come to register all my things in my name so that I won't later be accused of stealing them," he said. Liwa al-Tawhid has set up its own military police to deal with rebel fighters who step outside the law, but the well-armed and highly disciplined Islamist al-Nusra Front, noted for its integrity, holds the most public confidence. "When a rebel needs to be arrested, people turn to them because they are the only ones with sufficient power," said one rebel fighter. Al-Nusra is also called upon to adjudicate disputes among other brigades, for example over the distribution of ammunition or of the spoils of war. But while al-Nusra and Ahrar al-Sham are praised for their successes on the battlefield and for the humanitarian work they do, they also raise concerns about their political objectives. Al-Nusra has stated categorically that its aim is to establish an Islamic state in a post-Assad Syria. "The problem with our brothers in al-Nusra is that they want to put our women in veils overnight, as if this were Afghanistan," said the chief of a Kurdish rebel brigade. "We have never lived liked this. You can't impose sharia (Islamic law) on us just like that."