Temperature-based death time estimation in near equilibrium: Asymptotic confidence interval estimation.

Temperature based death time estimation (TDE) is severely limited in situations where body core temperature has almost decreased to ambient temperature. The TDE method of Marshall/Hoare and Henßge (MHH) defines a lower bound TK for body core temperature below which the time p.m. should be stated to be >10h only. A recent study (Potente et al., 2017 [10]) established a new method, called variance-bias-tradeoff (VBT) complementing MHH in constructing a right-side-half-infinite 97.5%-confidence interval for such 'near equilibrium'-situations. It seemingly proved the validity for all body core temperatures T<TK. The present study investigates VBT further and discovers that VBT-applicability has an upper limit in time since death. We show how to compute this upper limit explicitly in forensic casework and explain by the frequentist confidence interval probability interpretation why the former study (Potente et al., 2017 [10]) missed this upper limit.