From yementimes.com- 

In May, in Hajja governorate, a local tribal sheikh, a social leader in Yemen, used his jambia, a traditional Yemeni dagger, to threaten an employee at the government-owned Electricity Corporation over an alleged dispute. As a result, employees shut off electricity in the governorate for almost a week. The employees turned the electricity back on when the sheikh placed an oxen in front of the corporation. The animal, which was to be slaughterd, served as all the employees needed in terms of an apology and the blackouts came to an end.  

This serves as an example of Yemen’s entrenched tribal systems that provide a framework for conflict resolution outside the central state. Although Yemen operates govenment courts and has laws aimed at ensuring societal order, due to what many academic studies call a long history of tribal governance and arguably a weak central power, many of the country’s roughly 24 million inhabitants put their faith in a tribal justice systems when it comes to resolving disputes – some as minor as a verbal insults and some as sizeable as murder. 

According to a Yemen Polling Center study conducted at the end of 2012, 90 percent of tribal conflicts in Yemen are successfully solved by way of tribal arbitration.

...For some, tribal mediation is just easier and less time consuming than trying to elicit the help of often corrupt authorities explains Dr. Fuad Al-Salahi, sociology professor at Sana’a University. Al-Salahi points out that legal court proceedings can also be time consuming and bureaucratic. With chances of justice elusive at the hands of the state and in an attempt to prevent revenge killings that could spiral into longer feuds between tribes, sheikhs—who are at the top of the tribal heiarchy —are called into negotiate terms of a truce and justice.

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