Courts generally favor joint legal custody of minor children, giving both parents equal decision-making powers. But justice can be elusive in child custody trials and judges are not nearly as rational and predictable as many would like to believe.

Studies show several extra-legal factors can influence judicial decision-making, leaving the court vulnerable to mistakes.

Relying solely on evidence or testimony that's wisely crafted so the relevancy can be open to misinterpretation or easily brushed-over is perilous.

A growing trend in matrimonial cases has independent expert witnesses like physiatrists, lawyers and accountants playing a greater role by submitting comprehensive reports or testifying based on special knowledge or proficiency in a particular field that is significantly important to the case.

This extra tier of independent commentary helps the court understand the issues while lending transparency and integrity to the proceedings. So do non-expert witnesses, like a child's teacher, neighbor or grandparent who can provide the court with invaluable insight into family life and interrelationships. The court must be open to all arguments that support good parenting and child welfare.

Critics of expert witnesses say they are the last resort and should only testify when it necessarily helps juries.

Even so, the more information the court has the better the chances for an impartial decision.

Nicholas Casale has been involved in child custody matters as an expert and consultant to law firms regarding police procedure, involuntary committal to a comprehensive psychiatric emergency hospital under the NYS Mental Hygiene Law and investigative procedures regarding domestic incident reports. The author is a retired New York City police detective and principal partner at Casale Associates.