The formula for the demonic

"It is truly not Scripture alone that judges humans harshly. It is human beings who have pronounced the harshest and most severe judgment on themselves. And it is always better to fall into the hands of the Lord than into those of people, for his mercy is great. For when God condemns us, he at the same time offers his forgiving love in Christ, but when people condemn people, they frequently cast them out and make them the object of scorn. When God condemns us, he has this judgment brought to us by people—prophets and apostles and ministers—who do not elevate themselves to a level high above us but include themselves with us in a common confession of guilt. By contrast, philosophers and moralists, in despising people, usually forget that they themselves are human." - Herman Bavinck, Reformed Dogmatics

When the law is wielded minus the gospel it inevitably becomes demonic. It is also usually twisted and distorted and even turned upside-down, when wielded by unself-aware (or consciously evil) fallen human beings.

When you see phone video from Africa of a street justice scene you are seeing what law looks like wielded by unself-aware fallen man. Somebody accused of stealing will be set upon by a righteous crowd, kicked, stoned, set on fire. In false religion you see the same thing on a larger scale. In Islam you see all law and no gospel, and hence you see much crude violence and blood-letting in the name of 'righteousness.'

You see the same phenomenon in totalitarian states. Same law-minus-gospel at work. And twisted, distorted, perverted law at that. Law in the service of the goals of fallen angels and fallen man. The big end goal being human sacrifice (either suffering or death, or both) to the Kingdom of Satan. Genocide, if possible.

The main point is God's law, twisted, distorted, perverted, in the hands of ruling fallen angels on high and fallen man here on earth is demonic when it is without the necessary counterpoint of the gospel. Counterpoint: the combination of two or more independent melodies into a single harmonic texture...a complimenting item.