It is well known that Marx and Engels never produced a comprehensive theory of law, rights, or the state. At least nothing on a par with the critique of mainstream political economy in Capital and elsewhere. That said, issues of law, rights, and the state were not completely neglected in their works. From Marx’s engagement with rights in “On the Jewish Question”, the “Critique of the Gotha Program”, and elsewhere; to Engels in Origins of the Family, Private Property, and the State; and Marx again on the place and role of law in his discussion of the Factory Acts in the first volume of Capital, their works are replete with resources from which we can begin to piece together a Marxist theory of law.
One such resource is a comparatively brief but rich letter (still a “long read” by modern standards) that Engels sent to Conrad Schmidt in 1890.  In this missive Engels articulates three key principles that should inform any discussions we have about law, state, and rights from within the broad Marxist tradition. They are (i) the relative autonomy of the law; (ii) the decisive role of the economic structure of society in shaping law, state, et cetera; (iii) and, as a necessary complement to these ostensibly dichotomous positions, the need for a dialectical approach to the study of social phenomena.
The Relative Autonomy of Law
The Marxist tradition is often caricatured (or, more generously, misunderstood) as mechanical in its understanding of law. Often drawing upon a superficial reading of Marx’s statements in his famous preface to A Contribution to the Critique of Political Economy , many argue that Marxism posits a simplistic correspondence of law on the one hand and prevailing economic relations and dominant economic interests on the other. On this account, it is not until Nicos Poulantzas and others in the late twentieth century that the Marxist tradition develops a more complex understanding of the role of law in capitalist society.
As Engels’ letter to Schmidt shows, nothing could be further from the truth. In contrast to this mechanical caricature, Engels argues that
[i]n a modern state not only must the law correspond to the general economic situation and be its expression, it must of itself constitute a coherent expression that does not, by reason of internal contradictions, give itself the lie. And to achieve this, the fidelity with which economic conditions are reflected is increasingly thrown to the winds. All the more so for the rarity with which a statute book is the harsh, unmitigated, unadulterated expression of the domination of one class: this of itself would be contrary to the ‘concept of law’ … the course of the ‘law’s development’ has largely consisted … [in] the attempt to eliminate the contradictions arising from the direct translation of economic conditions into legal principles and to establish an harmonious legal system and, secondly, the fact that the influence and pressure of further economic developments repeatedly disrupt that system, involving it in fresh contradictions.
Engels makes it clear here that he understands law to be no mere reflection of dominant economic interests (i.e. no mechanical superstructure arising atop the economic base). Instead, he understands law and legal reasoning as having, to some degree, a life of their own.
On this understanding, the law develops as an ideological terrain, intimately connected to prevailing economic relations but preserving its own logic and rationality. It is to some extent autonomous from immediate, specific economic interests (“relatively autonomous”, in new money). It can, within limits, be engaged with and pushed to accommodate the interests of the marginalised and exploited masses (as with the Factory Acts), and also pushed to approximate better its own putative high ideals.
Back to the Base
However, while Engels accepts that the law develops a degree of autonomy under capitalism, he nonetheless reiterates the basic premise of historical materialism: in the final analysis, economic relations shape and structure law, rights, and the state. They impose ultimate horizons on both the form and content of law, and they are marked by certain structural tendencies, among them the preeminence of property rights, the insulation of capitalist class power, and the ideological legitimation of the status quo.
As Engels puts it, while the social division of labour engenders the sort of relative autonomy noted above, economic relations remain preeminent:
Where there is division of labour on a social scale, the various sections become mutually independent. Production is, in the final analysis, the decisive factor. But as soon as trade in products becomes independent of actual production, the former follows a trend of its own which is, by and large, undoubtedly dictated by production but, in specific cases and within the framework of that general dependence, does in turn obey laws of its own, laws inherent in the nature of this new factor; it is a trend having its own phases and reacting in turn on the trend of production.
Law, the rights of which it is comprised, and the state institutions whereby they are put into operation have a logic of their own, and they develop traditions and practices which those engaged with (or ensnared by) the law seek to reproduce. But this horizon of autonomy is shaped fundamentally by relations of social and economic reproduction.
Losing sight of this latter fact leads to reification–and, for our purposes, to variations on mainstream jurisprudence, political theory, and so on. Protagonists in these fields (lawyers, academics, and others trapped within Hart’s “internal point of view”) view the relatively autonomy of law and state power as primary, and lose sight of the structure imposed by economic relations of production. Again, as Engels puts it,
[t]he reflection of economic conditions as legal principles is likewise necessarily one that presents the image the wrong way up; it does so without the beholder being aware of it; the lawyer imagines he is dealing in a priori principles whereas they are, in fact, no more than economic reflections–and thus the whole thing is the wrong way up … this inversion which, in as much as it is not recognised, constitutes what we call an ideological view, reacts in its turn on the economic base and may, within certain limits, modify the same.
Thus, in this dense, rich letter, Engels sets out a complex understanding of the nature of law, state, and rights under capitalism, one that recognises both the relative autonomy of law and the ultimately structuring role of prevailing relations of production. The combination of such views may seem quixotic, were it not for the third key point Engels makes in this letter: the need for dialectical-materialist analysis.
The Dance of the Dialectic
One of the chief achievements of the Marxist tradition is the development of dialectical materialism as a method of analysis and inquiry–purged of Hegelian idealism, and put to work in the material world in the service of social transformation. As C. L. R. James once put it,
[t]oday when all thinkers are groping like drunken men, with all their points of support and reference gone, we have here a weapon [dialectical materialism] whose power and value was never so great as in the prevailing confusion. 
In a similar vein, Lukács argues that dialectics and contradiction lie at the heart of the Marxist tradition.  Dialectical-materialist reasoning, as opposed to rigid Aristotelian logic, comprises the core of Marxist analysis of social relations. Indeed, James goes so far as to argue that “it is impossible to deal with Marxism unless upon that basis”. 
Likewise, in his letter to Schmidt, Engels stresses the importance of dialectical reasoning and understanding. In caustically dismissing the arguments of some erstwhile peers, Engels argues that
[w]hat all these gentlemen lack is dialectics. All they ever see is cause on the one hand and effect on the other. But what they fail to see is that this is an empty abstraction, that in the real world such metaphysically polar opposites exist only in a crisis, that instead the whole great process takes place solely and entirely in the form of interplay–if of very unequal forces of which the economic trend is by far the strongest, the oldest and the most vital–and that here nothing is absolute and everything relative. So far as they are concerned, Hegel might never have existed.
The absence of dialectical analysis–an analysis that takes hold of the totality and interrelationship of all elements of the social order, and does not evade the centrality of contradiction–blinds us to the true character and complexity of social phenomena.
Instead, we need to ground our understanding of law, for present purposes, on an appreciation of the nature of real contradictions. How law and rights can, for example, be both constitutive of and place some modest limitations upon aspects of the extant system of social relations. How the state can be relatively autonomous, and also be a committee for managing the affairs of the bourgeoisie. In short, a dialectical understanding can help us to appreciate the messy reality of social relations, and the nature and role of law in capitalist society.
As the structural crisis of capitalism continues to unfold, and the irreducible contradictions of the system continue to stifle the lives of most people around the world, interest in Marx and the Marxist tradition will continue to grow. This imposes an obligation upon all of us to excavate and renovate all that is good in the Marxist tradition, and that contributes to our understanding of the world around us, with a view to changing it. As part of this process, the project of rethinking Marxist theories of law, state, and rights will benefit from revisiting the works of Marx, Engels, and others, and applying their valuable insights to the challenges we face today.
 Frederick Engels to Conrad Schmidt, 27 October 1890, in Marx-Engels Collected Works, vol. 49 (Lawrence & Wishart, 2010) 57; also available (in different translation) at https://www.marxists.org/archive/marx/works/1890/letters/90_10_27.htm.
 “‘Preface’ to A Contribution to the Critique of Political Economy” , in Karl Marx, Later Political Writings, ed. Terrell Carver (Cambridge: Cambridge University Press, 1996) 158; also available (in different translation) at https://www.marxists.org/archive/marx/works/1859/critique-pol-economy/preface.htm.
 C. L. R. James, “Education, Propaganda, Agitation” , in Martin Glaberman (ed.), Marxism for Our Times: C. L. R. James on Revolutionary Organization (Jackson: University Press of Mississippi, 1999) 4, 33.
 Georg Lukács, Lenin: A Study in the Unity of His Thought (London: New Left Books, 1970 ), 18.
 C. L. R. James, “Marxism For Our Times” , in Martin Glaberman (ed.), Marxism For Our Times: C. L. R. James on Revolutionary Organization (Jackson: University Press of Mississippi, 1999) 43, 44.
Paul O’Connell is Reader in Law and Associate Dean of Research in the Faculty of Law and Social Sciences at SOAS, University of London.