Can the other parent or a step-parent drastically change the child's appearance? (Parents have joint custody order)
NOTE: THIS SITUATION INVOLVED THE OTHER PARENT’S NEW SPOUSE (THE STEP-PARENT). IF THAT’S NOT THE CASE HERE, AND IT’S THE OTHER PARENT WHO DID IT, CHANGE THE LANGUAGE ACCORDINGLY
In general, joint custody can be structured in many different ways. Generally, in many situations, when parents have joint legal custody, it means that the parents need to consult with each other regarding major issues such as health, education and religion and come to a consensus about what to do. More minor decisions that arise when the child is at the parent’s house (such as what the child should eat, wear, bedtime, etc.) are often able to be made solely by the parent who is caring for the child at that time. However, sometimes what one parent thinks of a as a minor decision that s/he can make on his/her own is not so minor to the other parent - for example, changing the child’s hairstyle, piercing the child’s ears, etc. You specifically asked about what a step-parent can or cannot do. Since courts may not have jurisdiction over a step-parent, it may be hard to regulate a step-parent’s behavior but courts may often assume that the spouse of the step-parent already consented to the actions of the step-parent. So, for example, if a step-parent takes a child pierce her ears, the court may presume that the biological parent already discussed this with the step-parent and that the step-parent was acting as an agent of the parent. Then the issue becomes if the parent should be allowed to make the decision unilaterally (on his/her own) without consulting with the other parent. To find out how a court may view the actions of the other parent in your specific situation, you may want to talk to a lawyer for advice. Hopefully, the lawyer can tell you whether or not this is something that the courts normally allow either parent to decide on his/her own or whether or not the other parent violated the custody order by not checking with you first. Here is a link for lawyers, some of which are free or low-cost:LINK
Also, I wanted to mention that in situations where the joint custody order expects the parents to discuss issues and come to an agreement, the order may specify as to what the parents can do if the parents cannot agree on one decision - for example, going to a mediator, or a parenting coordinator within the court (if the state has one), or some other manner to resolve disputes. I am not sure what your order may or may not say about this.