Rarely, if ever, should joint legal custody be awarded if the parents cannot effectively communicate with each other concerning the best interest of the child, unless there is a strong potential for effective communication in the future.  The Court of Appeals in 1986 in the case of Taylor v. Taylor determined that the capacity of parents to communicate and reach shared decisions affecting the child's welfare to clearly be the most important factor in the determination of whether an award of joint legal custody (and also relevant to shared physical custody) is appropriate.  

Recently, in an unreported 2016 case, Santo v. Santo, the Court of Appeals affirmed a Circuit Court decision awarding joint legal custody to parents who could not effectively communicate.  The Santo case is the rare case in which the Court determined that joint legal custody was in the best interest of the children even though the parents could not effectively communicate with one another.  Joint custody was necessary so that both parents would remain informed and the children would have an opportunity to have a relationship with both parents.  The Court also held that no one major factor, such as ability to communicate, is more important than any of the other factors that are considered by the Court when making an award of joint custody.  

In order for joint custody to work when the parents were not able to effectively communicate to make shared decisions the Santo Court assigned final decision-making authority to each of the parents. In the event the parents were not able to reach shared decisions Mr. Santo was given final decision-making authority regarding education, religion and medical issues while Ms. Santo was given final decision-making authority regarding the children's therapist. In Santo, the Court of Appeals affirmed that trial courts in Maryland are authorized to use final decision-making provisions in joint custody determinations.