Final answer:
The Sixth Amendment guarantees the return of personal property retained as evidence in a sexual assault investigation after all legal proceedings are concluded.
Step-by-step explanation:
The reference for the return of personal property retained as evidence in a sexual assault investigation after all legal, adverse action, and administrative proceedings is the Sixth Amendment.
The Sixth Amendment guarantees the accused the right to a speedy and public trial, to be informed of the nature and cause of the accusation, to confront the witnesses against them, and to have the assistance of counsel for their defense. This amendment ensures due process of law and protects individuals from having their property taken without just compensation.
Therefore, once all the legal and administrative proceedings related to a sexual assault investigation are concluded, the rightful owner of the personal property retained as evidence should have it returned to them.