What he did was to produce the defence of a non-existent system which acted as a barrier to all legal, and much political, progress in the next half-century.

He gave men material without cause for satisfaction.
As a description of the existing government there is thus hardly an element of Blackstone's work which could stand the test of critical inquiry.

But even worse was its philosophy.

As Bentham pointed out, he was unaware of the distinction between society and government.

The state of nature exists, or fails to exist, with startling inconsistency.
Blackstone, in fact, was a Lockian who knows that Hume and Montesquieu have cut the ground from under his master's feet, and yet cannot understand how, without him, a foundation is to be supplied.