The Supreme Court back in 1886 dealt with a city code that placed the determination of a violation in the hands of the enforcer. This is the same thing that Divorce Custody Statutes do. They place complete discretion in the hands of one person alone. This is what the Supreme Court had to say about this concept.
“…the very idea that one man may be compelled to hold his life, or the means of living, or any material right essential to the enjoyment of life, at the mere will of another, seems to be intolerable in any country where freedom prevails, as being the essence of slavery itself.” — Yick Wo v. Hopkins, 118 US 356 – Supreme Court 1886
The best interests of the child is NOT a legal standard. It is nothing more than a fancy way of saying the “whim of a single judge” and the denial of any effective means of appeal over that judge’s whim. This is NOT acceptable in a country that prides itself on abiding by the rule of law.