Secondary Precepts:
In traditional Shi'i Islamic Jurisprudence, religious precepts can be generally divided into two groups: primary precepts and secondary precepts. Any subject, regardless of secondary consequences, in the first place belongs to the category of primary precepts. For example, it is religiously prohibited to eat meat that is not prepared according to religious guidelines under ordinary circumstances. But in extenuating circumstances, such as hardship and loss, secondary precepts can be implemented. For instance, a starving person may eat such meat. After the formation of the Islamic Republic, in accordance to the late leader's views, a third kind of law, known as state precepts ( ahkam-e hokoomatee ) was recognized in our legal system. In other words, a religious government acting as religious guardian, can issue a law or declare something temporarily necessary or prohibited, according to exigencies and interests of Islamic society. Therefore, in our legal system there exists three religious sources for issuing precepts: the nature of the subject itself regardless of secondary consequences, secondary consequences and emergency, and expedience.
The above explanation was taken from: http://www.badjens.com/alireza.html