J-1 Consular Application
Technically the law allows you to apply for a J-1 at any U.S. consulate you choose. However, from a practical standpoint your case will be given greatest consideration at the consulate in your home country. Applying in some other country creates suspicion about your motives for choosing their consulate. Often, when an applicant is having trouble at a home consulate he will seek a more lenient office in some other country. This practice of consulate shopping is frowned on. Unless you have a very good reason for being elsewhere (such as a temporary job assignment in some other nation), it is smarter to file your visa application in your home country.
Furthermore, if you have been present in the U.S. unlawfully, in general you cannot apply as a third-country national. Even if you overstayed your status in the U.S. by just one day, your visa will be automatically cancelled and you must return to your home country and apply for the visa from that consulate. There is an exception. If you were admitted to the U.S. for the duration of your status (indicated by a “D/S” on your I-94 form) and you remained in the U.S. beyond the authorized period of stay, you may still be able to apply as a third-country national. Under current regulations, you will be barred from third-country national processing only if an immigration judge or USCIS officer has determined that you were unlawfully present. Because of the ambiguity, you may find that your success in applying as a third-country national will depend on your country, the consulate and the relative seriousness of your offense.
You may not file an application for a J-1 visa at a consulate until a DOS-approved exchange visitor program sponsor has given you a Certificate of Eligibility, Form DS-2019. On entering the U.S. with your new J-1 visa, you will be given an I-94 card. It will be stamped “D/S” indicating that you can stay until the completion of your program. As a practical matter, however, you are permitted to remain up to the expiration date on your Form DS-2019 Certificate of Eligibility. Each time you exit and reenter the U.S., you will get a new I-94 card.