Court of Appeals
In Texas, we call it a court of appeals, not a court of appeal. Thus the possessive becomes a problem. One commenter and others I have consulted prefer this form for a singular possessive:
- the court of appeals' opinion
- the court of appeals's opinion
- the opinion of the court of appeals
- the courts of appeals
As you can see, the exciting issues in legal-writing are endless. Here I am. Rock me like a hurricane.