Most state courts will at least entertain a teenager's wishes when it comes to custody decisions in a divorce, and Massachusetts is no exception. The state's laws only give your child a say, however. His preference may be acknowledged if he's old enough, but it will be taken in context with a lot of other factors. The judge is not obligated to rule the way your child wants him to.
Interview With the Judge
Children who are at least 14 years old have a right to state their opinions directly to the judge. If your child wants to do this, a Massachusetts court must allow it. Your child won't be put on the stand to testify in the middle of your divorce trial, but would meet with the judge privately instead, typically in the judge's chambers. The judge is then permitted to take your child's feelings into consideration, just as he would consider testimony given in the courtroom.
Using a Guardian ad Litem
When a divorce is particularly contentious, or if you or your spouse are making serious allegations against the other such as neglect or abuse, a Massachusetts court may appoint a guardian ad litem. These professionals are sometimes referred to as GALs. A GAL is assigned to protect your child's interests, and will interview him and report his findings back to the judge. Most Massachusetts divorce cases do not involve GALs, but you can request that the court appoint one as part of your proceedings, if you think your situation warrants it.