Estudio de los efectos del anclaje en razonamientos judiciales en casos de disputa por la guarda y custodia

Judicial judgment and decision making should be sus­tained in formal or statistical reasoning, avoiding biased reasoning. Thus, judicial reasoning should not contain any bias. A profusely studied source of bias is anchorage implying a cognitive saving by accepting the initial hy­pothesis without confirming it and rejecting other infor­mation or alternative hypotheses though they may be rel­evant to the task at hand. As for knowing the prevalence and effects of anchored sentences in family cases’ judi­cial sentences, 811 Spanish custody dispute sentences were randomly selected from the CENDOJ data base. Anchorage was measured through initial claimant in child custody dispute (first instance court) or prior judi­cial decision-making (appeal court). The results stated that 70.2 % of the judicial sentences were anchored. A systematic content analysis of the sentences gave support to the hypothesis that anchorage provides judges and courts a skill to save cognitive activity (about 12 %). Moreover, anchored sentences contained significantly fewer reasoning favourable to custody; fewer idiosyn­cratic information i.e., own reasoning of the judge; and fewer contextual information i.e., less evidence-based. The implications for judicial judgment and decision are discussed, as well as the possibilities to control the an­chorage prevalence in judicial sentences. ResumenLa formación de juicios y la toma de decisiones judicia­les deberían estar sustentadas en razonamientos formales o estadísticos, y no en razonamientos sesgados de modo que no deberían contener razonamientos sesgados. Una fuente de sesgo profusamente estudiada en la literatura es el anclaje que implica un ahorro cognitivo al aceptar la hipótesis inicial sin confirmarla y rechazar información o hipótesis alternativas, aunque puedan resultar relevantes para el juicio o decisión. Para conocer de la prevalencia y los efectos del anclaje en sentencias judiciales de casos de familia, seleccionamos al azar 811 sentencias en disputa por la guarda y custodia de la base de datos del CENDOJ. El anclaje se midió a través de la demanda ini­cial en la disputa por la custodia (juzgado de familia) o en la decisión del tribunal previo (apelaciones). Los re­sultados mostraron que el 70.2 % las decisiones estaban ancladas. Un análisis de contenido sistemático de las sentencias prestó apoyo a la hipótesis de que el anclaje sirve a jueces y tribunales como herramienta para el aho­rro cognitivo (alrededor del 12 %). Además, las senten­cias ancladas contenían significativamente menos razo­namientos favorables a la custodia; menos información idiosincrásica, o sea, razonamientos propios del juez; y menos información contextual, esto es, menos prueba ba­sada en evidencia. Se discuten las implicaciones de los resultados para la formación de juicios y toma de deci­siones judiciales, así como las opciones de mitigar sus efectos.AbstractJudicial judgment and decision making should be sus­tained in formal or statistical reasoning, avoiding biased reasoning. Thus, judicial reasoning should not contain any bias. A profusely studied source of bias is anchorage implying a cognitive saving by accepting the initial hy­pothesis without confirming it and rejecting other infor­mation or alternative hypotheses though they may be rel­evant to the task at hand. As for knowing the prevalence and effects of anchored sentences in family cases’ judi­cial sentences, 811 Spanish custody dispute sentences were randomly selected from the CENDOJ data base. Anchorage was measured through initial claimant in child custody dispute (first instance court) or prior judi­cial decision-making (appeal court). The results stated that 70.2 % of the judicial sentences were anchored. A systematic content analysis of the sentences gave support to the hypothesis that anchorage provides judges and courts a skill to save cognitive activity (about 12 %). Moreover, anchored sentences contained significantly fewer reasoning favourable to custody; fewer idiosyn­cratic information i.e., own reasoning of the judge; and fewer contextual information i.e., less evidence-based. The implications for judicial judgment and decision are discussed, as well as the possibilities to control the an­chorage prevalence in judicial sentences.