Article 160: The State supervises the whole affairs of industry. It directly undertakes those industries which are connected to whatever is part of the public property.
This article has two halves: firstly, supervision over the whole of industry; secondly, directly undertaking some of the industrial affairs. As for the first half its evidence is that the Messenger consented to private ownership of factories such as those for shoes, swords, clothes and other things:
«أَنَّ النَّبِيَّ اصْطَنَعَ خَاتَمًا»
“The Prophet had a ring made for him” (reported by Al-Bukhari from ‘Abd Allah Bin Umar) and:
«أَنَّهُ اسْتَصْنَعَ المِنْبَرَ»
“He had a pulpit made” (reported by Al-Bukhari from Sahl Bin Sa’d Al-Sa’idi). This indicates that factories are run by private individuals and not the State. Therefore, it is not different to agriculture. However, it is part of the managing of the affairs that Allah (swt) obligated upon the State with the words of the Prophet
«الإِمَامُ رَاعٍ وَهُوَ وَمَسْؤُولٌ عَنْ رَعِيَّتِهِ»
“The Imam is a guardian and he is responsible for his subjects” (reported by Al-Bukhari from ‘Abd Allah Bin Umar), and so the State has to generally supervise the industrial issues by organising what is permitted according to the various styles which would assist the advancement of production, and by opening markets for it, and making sure raw materials are available, and so on.
As for the second half, the evidence for it is the Shari’ah principle: “The factory takes the rule of what it produces”; it is reported from Anas that:
«لَعَنَ اللَّهُ الْخَمْرَ وَشَارِبَهَا وَسَاقِيَهَا وَبَائِعَهَا وَمُبْتَاعَهَا وَعَاصِرَهَا وَمُعْتَصِرَهَا وَحَامِلَهَا وَالْمَحْمُولَةَ إِلَيْهِ»
“Allah has cursed wine, its drinker, its server, its seller, its buyer, its presser, the one for whom it is pressed, the one who conveys it, and the one to whom it is conveyed.” (reported by Abu Dawud from Ibn Umar and authenticated by Ibn Al-Sakn). And so the production of pressing the grapes for alcohol was prohibited by the Messenger because it produces alcohol, even though pressing is permitted; so the production took the rule of the material that it produced, and this is general. Based upon this, the factory takes the rule of the material it produces, and so the factories that produce anything considered part of public property are part of public property, since they take the rule of what they produce.
Public property belongs to all the Muslims, and it is not allowed for an individual or group of individuals to independently own it such that others are prevented from its ownership. From this understanding, the Khalifah is the one who manages these factories and prevents private ownership of them, since private ownership would prevent others from being able to gain ownership, and, therefore, the State has to directly manage the factories which are part of public property, such as those for oil extraction, steel and gold mining and so on. However, it is treated as a specific interest in terms of its income, expenditure and the rest of its affairs, and its profits are placed in the Bayt Al-Mal in a section specified for it, since it is not considered to be part of the State property, but rather part of public property.