Score based procedures for the calculation of forensic likelihood ratios – Scores should take account of both similarity and typicality

Score based procedures for the calculation of forensic likelihood ratios are popular across different branches of forensic science. They have two stages, first a function or model which takes measured features from known-source and questioned-source pairs as input and calculates scores as output, then a subsequent model which converts scores to likelihood ratios. We demonstrate that scores which are purely measures of similarity are not appropriate for calculating forensically interpretable likelihood ratios. In addition to taking account of similarity between the questioned-origin specimen and the known-origin sample, scores must also take account of the typicality of the questioned-origin specimen with respect to a sample of the relevant population specified by the defence hypothesis. We use Monte Carlo simulations to compare the output of three score based procedures with reference likelihood ratio values calculated directly from the fully specified Monte Carlo distributions. The three types of scores compared are: 1. non-anchored similarity-only scores; 2. non-anchored similarity and typicality scores; and 3. known-source anchored same-origin scores and questioned-source anchored different-origin scores. We also make a comparison with the performance of a procedure using a dichotomous “match”/“non-match” similarity score, and compare the performance of 1 and 2 on real data.     

Criminogenic needs and human needs: A theoretical model

Over the last two decades, empirical evidence has increasingly supported the view that it is possible to reduce reoffending rates by treating or rehabilitating offenders rather than simply punishing them. In fact, this shift from a punishment to a rehabilitation model is arguably one of the most significant events in modern correctional policy. Criminogenic needs, dynamic risk factors, have been the focus of a considerable amount of research and are viewed as primary intervention targets. Drawing from the correctional, psychological, philosophical, and social policy literature, we distinguish between instrumental and categorical needs. The latter are derived from assumptions about human nature and provide the theoretical grounds for the former, as well as for criminogenic needs. We argue that an enriched concept of needs embedded in the notion of human well being, can provide a coherent conceptual basis for rehabilitation and also avoid the problems apparent in the concept of criminogenic needs. From this perspective, criminogenic needs are usefully construed as the internal and external obstacles associated with need distortion. Therefore, they are directly linked to basic need distortion and the absence of the internal and external conditions necessary for a person to lead a fulfilling life. Finally, we outline a possible framework utilising categorical needs and discuss the clinical and policy implications of our perspective.     

Bacterial Degradation of Risperidone and Paliperidone in Decomposing Blood

The stability of two benzisoxazole antipsychotics was determined in vitro in decomposing porcine blood inoculated with bacteria, utilizing a high‐performance liquid chromatography with ultraviolet and fluorescence detection method for drug quantitation. Stability experiments for risperidone and paliperidone were conducted at 7, 20 and 37°C for 4 days using sterile and bacterially inoculated porcine blood. The drugs were stable in sterile blood at each temperature and in inoculated blood at 7°C, but degraded significantly in inoculated blood at 20 and 37°C. Complete loss occurred within 2 days when incubated at 37°C. The benzisoxazole‐cleaved degradation products for both drugs were identified as 2‐hydroxybenzoyl‐risperidone and 2‐hydroxybenzoyl‐paliperidone utilizing liquid chromatography quadrupole‐time‐of‐flight mass spectrometry and accurate mass measurements. The degradation products have been found in postmortem case studies, including one case where risperidone and paliperidone were not detected, indicating complete conversion can occur in situ.     

Decentralization and initiative: TVA returns to its roots

The Tennessee Valley Authority, a federal corporation established by Congress in 1933, is charged with the integrated regional development of the Tennessee Valley's resources, including flood control, navigation, reforestation and proper use of marginal lands, electricity generation, and agricultural and economic development. TVA's early leaders, especially David E. Lilienthal and Gordon R. Clapp, articulated a doctrine of “grass roots democracy” and “decentralization” that protected TVA from rival federal bureaucracies and provided greater flexibility and freedom in carrying out TVA's multi-purpose mission. This doctrine also led to innovations in the professionalization of TVA' s highly skilled and diverse workforce. Clapp, a recognized leader in public administration, promoted employee initiative, easy access to top management, multi-disciplinary teamwork, labor/management collaboration, and partnerships with states and localities that took account of local needs and values. The development of joint cooperative councils and conferences, along with other initiatives, were visible manifestations of this “democratic method of administration.”

In the aftermath of Clapp's chairmanship that ended in 1954, TVA placed principal emphasis on expanding its electric power system and moved to a more traditional bureaucratic structure of tight control, accountability, and discipline. The crisis of survival that developed in the 1980s had its roots in a growing isolation, rigidity, and decline of professional excellence that was an outgrowth of this new bureaucracy. The current TVA chairman, Marvin T. Runyon, is leading a recovery effort to restore TVA's competitiveness. This effort recalls the vision and values of “grass roots democracy” and “decentralization” espoused by Clapp and Lilienthal. Although coming to TVA with no prior experience in the public sector, Runyon's emphasis on customer service and satisfaction, quality products, teamwork, creative problem solving, employee empowerment, and being “the best” recalls the professionalism and professionalization of the public administrators who led TVA in its early years.     

Book notes

Habitat : Human Settlements in an Urban Age, Angus McGunn, Pergamon Press, 1978, pp. 272, price unknown.

Decision Making for Energy Futures, David Pearce, Lynne Edwards and Geoff Beuret, Macmillan, 1979, pp. 296, £10.00.

Party Politics in Local Government: Officers and Members, Royal Institute of Public Administration, Policy Studies Institute, 1980, pp. 50, £2.50.

District Trends 1980, City of Bradford Metropolitan Council, 1980, pp. 45, free.

Housing the Disabled, John Hunt and Lesley Hayes, Torfaen Borough Council (with the support of Cwmbran Development Corporation), 1980, pp.204, £3.95 (paperback).

The West Riding County Council, 1889–1974 Historical Studies, B. J. Barber and M. W. Beresford, West Yorkshire Metropolitan County Council, 1979, pp. 262, price unknown.

Public Administration: The Political Environment, Roger Stacey and John Oliver, MacDonald and Evans (BEC Books), 1980, pp. 296, £4.95 (paperback).

How to Run Committees and Meetings, Michael Locke, Papermac (Macmillan Press), 1980, pp. 190, £2.95 (paperback), £10.00 (hardback).

The Politics of Positive Discrimination: An Evaluation of the Urban Programme, 1967–77, John Edwards and Richard Batley, Tavistock Publications Ltd., 1978, pp. 287, £4.25 (paperback).

Urban Deprivation and the Inner City, Colin Jones (Editor), Croom Helm, 1979, pp. 218, £9.95 (hardback).

Urban Harvest: Urban Renewal in Retrospect and Prospect, Stanley Mill‐ward (Editor), Geographical Publications Ltd., 1977, pp. 266, £8.25 (hardback).     

Diesel fumes do kill: a case of fatal carbon monoxide poisoning directly attributed to diesel fuel exhaust with a 10-year retrospective case and literature review*

While it is known that diesel fuel combustion engines produce much lower concentrations of carbon monoxide (CO) than gasoline engines, these emissions could certainly generate lethal ambient concentrations given a sufficient amount of time in an enclosed space and under suitable environmental conditions. The authors report a case of CO poisoning which was initially referred for autopsy as a presumed natural death of a truck driver found in the secure cab of a running diesel tractor trailer truck. Completion of the preliminary investigation ascribed death to complications of ischemic heart disease (IHD), pending toxicological analysis that included quantification of CO. When the toxicology results showed lethal blood COHbg, the cause of death was re-certified as CO intoxication secondary to inhalation of (diesel) vehicular exhaust fumes. Because of the unique source of fatal CO intoxication in this case, the contributory IHD and the possible contaminants in the putrefied blood, a 10-year retrospective review was conducted on all nonfire related CO deaths autopsied (n = 94) at the Office of the Chief Medical Examiner in Louisville, KY from 1994 to 2003. For validation of the COHbg detection method used by the Kentucky Office of Forensic Toxicology (KYOFT), blood samples from these cases along with controls were submitted to three laboratories using various analytical methods yielding no statistically significant differences. Lastly, an extensive literature review produced no scientifically reported cases of fatal CO poisoning attributed to diesel fuel exhaust.