A more thorough explanation:

S.D.

S.D. is an abbreviation for Southern District, which refers to one of the judicial districts in the United States.

1. The case was heard in the S.D. of New York.

2. The defendant was indicted in the S.D. of Texas.

These examples show how S.D. is used to refer to a specific judicial district in the United States. The first example mentions the S.D. of New York, while the second example mentions the S.D. of Texas. By using S.D., it is clear which district is being referred to without having to write out the full name of the district each time.