Rule 28.Persons before whom depositions may be taken

Rule 28(a) covers depositions taken within the United States or its territories: they go before an officer authorized to administer oaths under the law of the place where the examination happens, or before a person the court appoints, who then has the power to administer oaths and take testimony. Rules 30, 31, and 32 use the word "officer" to mean either of those people, or a person the parties designate under Rule 29.

Rule 28(b) covers depositions taken in a foreign country, and gives four routes: under an applicable treaty or convention, under a letter of request (whether or not it's called a letter rogatory), on notice before a person authorized to administer oaths where the examination is held, or before a person the court commissions. A commission or letter of request issues on application and notice, on terms that are just and appropriate, and a party doesn't have to show that taking the deposition another way would be impracticable or inconvenient before getting one. Evidence obtained through a letter of request isn't excluded just because it isn't a verbatim transcript, wasn't taken under oath, or otherwise departs from how a deposition would run inside the United States.

Rule 28(c) disqualifies anyone who is a relative, employee, attorney, or counsel of a party, or a relative or employee of that attorney or counsel, or who has a financial interest in the action, from presiding over a deposition in that case. Rule 28(d) lets the notice or commission identify the officer by name or descriptive title, and lets a letter of request address the appropriate authority in the named state or country.