Effects of an alibi witness's relationship to the defendant on mock jurors' judgments.

Two studies tested the impact of an alibi witness's relationship to a defendant on the perceived credibility of that witness. In the first study, 291 mock jurors estimated the frequency with which individuals would invent alibis, the frequency they themselves would do so, and the frequency of interpersonal contact among individuals of varying relationships. The degree of relationship between an alibi witness and a defendant remained a predictor of witness credibility when contact frequency was controlled. In the second study, 512 mock jurors were randomly assigned to case scenarios. Skepticism toward witnesses who are biologically or affinally related to a defendant was greater than skepticism toward a socially linked witness. Both studies supported predications from kinship theory and reciprocal altruism.

Blood lead in the 21st Century: The sub-microgram challenge.

In the US the dominant sources of lead through much of the 20th Century (eg, vehicular emissions, plumbing, household paint) have been significantly diminished. The reductions in adult and pediatric average blood lead levels in the US have been extraordinary. Progress continues: the US Environmental Protection Agency recently developed a new air standard for lead. In the 21st Century, the average blood lead level in a society may be seen as a marker of the status of their public's health. However, the threat of lead exposure remains a significant public health problem among subpopulation groups in the US and in many less developed countries. This paper examines some of the specific issues involved in the reduction of blood lead in a post-industrial era. These involve the control of the remaining exogenous primary sources, both general (eg, industrial emissions) and specific (eg, at-risk occupations), exogenous secondary sources (eg, contaminated urban soils, legacy lead-based paints), an endogenous source (ie, cumulative body lead burden) and emergent sources.