A more thorough explanation:

Definition: In re is a Latin phrase that means "in the matter of." It is used in legal documents to refer to a case, especially when there is no opposing party. For example, "In re Estate of Ruth Bentley" might be used to refer to a probate case about the estate of Ruth Bentley. The use of "in re" refers to the object or person that is the primary subject of the case. It is commonly used in probate proceedings and in juvenile courts.

Examples:

• "In re Gault" is a case regarding a juvenile criminal defendant.
• "In re Marriage of Smith" might be used to refer to a divorce case where there is no dispute between the parties.
• "In re City of New York" might be used to refer to a case involving a city government.

These examples illustrate how "in re" is used to refer to a case where there is no opposing party or where the proceeding is in rem or quasi in rem and not in personam. It is a way to identify the primary subject of the case and distinguish it from other cases with similar names.