What works in intelligence

This report analyses police intelligence practice in Britain through the lens of the ‘what works?’ concept. It is based on a survey of a self-selected group of intelligence staff together with interviews with a random sample of their number. Participants reflected on: their skills and abilities; their training; their successes and their failures; and the utility of the structures and processes within which they operated. We found that respondents broadly agreed on what contributed to effective practice. For example, analysts, intelligence officers and managers ranked a skilled workforce as of greatest import. Human intelligence (HUMINT); operational teams, capable of responding quickly to intelligence; information technology; and plentiful sources of intelligence in their communities, were consistently ranked the top four significant factors in their successes. At the same time, we conclude that while the ‘what works?’ approach has some value when applied to policing, there are clear limits to its explanatory power. We conclude that the ‘what works?’ approach also raises important, albeit largely ignored, questions about institutional memory and identity and that institutional and cultural factors represent significant barriers to the adoption of evidence-based practice in policing

Unstable decay and state selection II

The decay of unstable states when several metastable states are available for occupation is investigated using path-integral techniques. Specifically, a method is described which allows the probabilities with which the metastable states are occupied to be calculated by finding optimal paths, and fluctuations about them, in the weak noise limit. The method is illustrated on a system described by two coupled Langevin equations, which are found in the study of instabilities in fluid dynamics and superconductivity. The problem involves a subtle interplay between non-linearities and noise, and a naive approximation scheme which does not take this into account is shown to be unsatisfactory. The use of optimal paths is briefly reviewed and then applied to finding the conditional probability of ending up in one of the metastable states, having begun in the unstable state. There are several aspects of the calculation which distinguish it from most others involving optimal paths: (i) the paths do not begin and end on an attractor, and moreover, the final point is to a large extent arbitrary, (ii) the interplay between the fluctuations and the leading order contribution are at the heart of the method, and (iii) the final result involves quantities which are not exponentially small in the noise strength. This final result, which gives the probability of a particular state being selected in terms of the parameters of the dynamics, is remarkably simple and agrees well with the results of numerical simulations. The method should be applicable to similar problems in a number of other areas such as state selection in lasers, activationless chemical reactions and population dynamics in fluctuating environments.Comment: 28 pages, 6 figures. Accepted for publication in Phys. Rev.

The road not taken: understanding barriers to the development of police intelligence practice

To better understand police intelligence practice, we examined practitioners’ views of their work and their relations with the wider law enforcement community. We surveyed intelligence staff (n = 110) and interviewed a random sample of respondents (n = 12). Our analysis suggested that traditionalism and the dominant action-oriented culture limit the organization’s understanding of intelligence practice. Largely, the focus in that context has been on street cops’ propensity to reject reflection in favor of action, but intelligence practitioners need also look to themselves. Too often, the philosophy of “need to know” is prioritized over its antithesis, “dare to share.” Though perceived by practitioners as low-risk and consistent with organizational norms, we argue that inappropriately applied “need to know” is the enemy of efficiency and real accountability, offering low levels of reward and discouraging the kinds of partnership, reciprocity, and multi-directional knowledge transfer that policing needs to be successful in the information age. We reconceptualized an interactivity/isolationism continuum, used in the natural sciences, to help interpret that phenomenon. We argue that isolationism is but one factor in a complex organizational dynamic, but it is a significant one because it can subtly limit the influence and reach of the intelligence milieu in previously unacknowledged ways

Continuum Derrida Approach to Drift and Diffusivity in Random Media

By means of rather general arguments, based on an approach due to Derrida that makes use of samples of finite size, we analyse the effective diffusivity and drift tensors in certain types of random medium in which the motion of the particles is controlled by molecular diffusion and a local flow field with known statistical properties. The power of the Derrida method is that it uses the equilibrium probability distribution, that exists for each {\em finite} sample, to compute asymptotic behaviour at large times in the {\em infinite} medium. In certain cases, where this equilibrium situation is associated with a vanishing microcurrent, our results demonstrate the equality of the renormalization processes for the effective drift and diffusivity tensors. This establishes, for those cases, a Ward identity previously verified only to two-loop order in perturbation theory in certain models. The technique can be applied also to media in which the diffusivity exhibits spatial fluctuations. We derive a simple relationship between the effective diffusivity in this case and that for an associated gradient drift problem that provides an interesting constraint on previously conjectured results.Comment: 18 pages, Latex, DAMTP-96-8

A central role for hepatic conventional dendritic cells in supporting Th2 responses during helminth infection

Dendritic cells (DCs) are the key initiators of T-helper (Th) 2 immune responses against the parasitic helminth Schistosoma mansoni. Although the liver is one of the main sites of antigen deposition during infection with this parasite, it is not yet clear how distinct DC subtypes in this tissue respond to S. mansoni antigens in vivo, or how the liver microenvironment might influence DC function during establishment of the Th2 response. In this study, we show that hepatic DC subsets undergo distinct activation processes in vivo following murine infection with S. mansoni. Conventional DCs (cDCs) from schistosome-infected mice upregulated expression of the costimulatory molecule CD40 and were capable of priming naive CD4+ T cells, whereas plasmacytoid DCs (pDCs) upregulated expression of MHC class II, CD86 and CD40 but were unable to support the expansion of either naive or effector/memory CD4+ T cells. Importantly, in vivo depletion of pDCs revealed that this subset was dispensable for either maintenance or regulation of the hepatic Th2 effector response during acute S. mansoni infection. Our data provides strong evidence that S. mansoni infection favors the establishment of an immunogenic, rather than tolerogenic, liver microenvironment that conditions cDCs to initiate and maintain Th2 immunity in the context of ongoing antigen exposure

In search of community history

This editorial response to the preceding article by Dennis Mills addresses the meaning of community history. Rejecting an over-tight definition, we argue for a methodologically distinct community history, combining a micro-historical approach with a sensitivity to the discursive construction of the term 'community'. Furthermore the role of family and community historians should be to adapt a critical stance towards contemporary meanings of both past 'communities' and past 'families'. The article concludes that Withington and Shephard's schema for approaching the history of 'community' offers a practical way forward for the family and community historian

Type I interferon is required for T helper (Th) 2 induction by dendritic cells

Type 2 inflammation is a defining feature of infection with parasitic worms (helminths), as well as being responsible for widespread suffering in allergies. However, the precise mechanisms involved in T helper (Th) 2 polarization by dendritic cells (DCs) are currently unclear. We have identified a previously unrecognized role for type I IFN (IFN-I) in enabling this process. An IFN-I signature was evident in DCs responding to the helminth Schistosoma mansoni or the allergen house dust mite (HDM). Further, IFN-I signaling was required for optimal DC phenotypic activation in response to helminth antigen (Ag), and efficient migration to, and localization with, T cells in the draining lymph node (dLN). Importantly, DCs generated from Ifnar1-/- mice were incapable of initiating Th2 responses in vivo. These data demonstrate for the first time that the influence of IFN-I is not limited to antiviral or bacterial settings but also has a central role to play in DC initiation of Th2 responses