Letters Rogatory are formal requests to serve legal documents, sent to the court of a foreign state where a party or a witness resides. Several states which are not privies to the international treaties on process service make use of this system.
The system works when the court, where a case is pending or initiated, sends a formal request to the court in another state which exercises territorial jurisdiction over the place where the party or witness resides.
Letters Rogatory is only honored by countries having diplomatic relations with the United States. However, some countries which do not have any diplomatic ties with the U.S. accept these requests for reasons of international comity.
However, Letters of Rogatory does not guarantee that the receiving state will grant and take action on the request. Bear in mind that these are mere requests. The prerogative to act on these formal requests still lies with the receiving state. But, more often than not, these are granted out of comity or in order to avoid similar retaliation from the sending state.
Extraction of Evidence
Letters Rogatory are used in order to haul out evidence or testimonies from witnesses who are residents of another state. When the formal request is sent to the court of the receiving state, the court sends its officials or employees to extract from the witness the evidence by way of taking depositions.
Depositions are answers or testimonies given by a witness who is not available to take the witness stand. In adopting this manner of acquiring evidence, the counsel sends to the court the list of questions he wanted to ask the witness. The court on the other hand, sends its employee or officer to take the deposition or statement of the witness based on the prepared list of questions.
The depositions taken from the witness will be sent back to the sending state where the court trying the case sits. The process may take 6 months or more depending on the municipal laws of the receiving state.
Process Service
Letters Rogatory are best used in international process service. As a general rule, a U.S. court can only serve notices and other legal documents within the jurisdiction of the U.S. courts. U.S. courts cannot serve judicial notices and documents outside its territorial jurisdiction. Due to this dilemma, the United States and other states makes use of the process of sending Letters Rogatory which is actually a request for permission addressed to the receiving state where the person upon whom service is to be made resides.
These requests are made to go through diplomatic channels between the sending state and the receiving state. It is also a necessity that all documents be translated to the official language of the receiving state in order to efficiently facilitate the service of the document.
Once the document is served, a report or certificate of the service shall be sent back to the sending state in a reverse manner.
Hague Service Convention and Inter-American Convention
The Hague Service Convention and Inter-American Convention are international process service treaties where the United States is one of the signatories. These treaties provide for a systematic method of international process service.
Under the provisions of the Hague Service Convention, each member states are required to put up a Central Authority which is tasked to receive all Letters Rogatory from other member states. On the other hand, the Inter-American Convention requires that Letters Rogatory be signed and certified by the clerk of the court where the case is pending. In both of these treaties, a required document or form suffices the requisite for Letters Rogatory.

