For example, in Minnesota, the factors are stated as follows:
"The best interests of the child" means all relevant factors to be considered and evaluated by the court including:
(1) the wishes of the child's parent or parents as to custody;
(2) the reasonable preference of the child, if the court deems the child to be of sufficient age to express preference;
(3) the child's primary caretaker;
(4) the intimacy of the relationship between each parent and the child;
(5) the interaction and interrelationship of the child with a parent or parents, siblings, and any other person who may
significantly affect the child's best interests;
(6) the child's adjustment to home, school, and community;
(7) the length of time the child has lived in a stable, satisfactory environment and the desirability of maintaining
continuity;
(8) the permanence, as a family unit, of the existing or proposed custodial home;
(9) the mental and physical health of all individuals
involved; except that a disability, as defined in section 363A.03, of a proposed custodian or the child shall not be
determinative of the custody of the child, unless the proposed custodial arrangement is not in the best interest of the child;
(10) the capacity and disposition of the parties to give the child love, affection, and guidance, and to continue educating and raising the child in the child's culture and
religion or creed, if any;
(11) the child's cultural background;
(12) the effect on the child of the actions of an abuser, if related to domestic abuse, as defined in section 518B.01, that has occurred between the parents or between a parent and
another individual, whether or not the individual alleged to have committed domestic abuse is or ever was a family or household member of the parent; and
(13) except in cases in which a finding of domestic abuse as defined in section 518B.01 has been made, the disposition of each parent to encourage and permit frequent and continuing
contact by the other parent with the child.
The court may not use one factor to the exclusion of all others. The primary caretaker factor may not be used as a presumption in determining the best interests of the child. The
court must make detailed findings on each of the factors and explain how the factors led to its conclusions and to the determination of the best interests of the child.
In Wisconsin, there is a presumption for maximizing time with each parent that is often translated into a presumption for joint physicalplacement. The factors to be considered along with that presumption are similar, but not the same as Minnesota.
Its decision must weigh following factors set out in the statute:
(1) The wishes of the child's parent or parents.
(2)The wishes of the child, which may be communicated by the child or through the child's guardian ad litem or other appropriate professional.
(3)The interaction and interrelationship of the child with his or her parent or parents, siblings, and any other person who may significantly affect the child's best interest.
(4)The child's adjustment to the home, school, religion and community.
(5)The mental and physical health of the parties, the minor children and other persons living in a proposed custodial house-hold.
(6)The availability of public or private child care services.
(7)Whether one party is likely to unreasonably interfere with the child's continuing relationship with the other party.
(8)Whether there is evidence that a party engaged in abuse.
(9)Whether there is evidence of interspousal battery.
(10)Whether either party has or had a significant problem with alcohol or drug abuse.
(11)Such other factors as the court may in each individual case determine to be relevant.