The San Bernardino attacks this month put the spotlight on a type of visa issued to a wide swath of foreigners, from camp counselors to physicians, and how easy it is for recipients to remain in the U.S. after the visa has expired.
A Russian woman who married Enrique Marquez Jr., the man accused of buying rifles used in the Dec. 2 attack, entered the U.S. six years ago on a three-month educational-exchange visa, known as a J-1 visa.
Once that visa expired, she remained for several years in the U.S. without legal status, according to law-enforcement officials.
In late 2014, Mariya Chernykh and Mr. Marquez were married, according to Riverside County, Calif., records. Last week, Mr. Marquez was charged with entering into a sham marriage to enable her to apply for permanent residency in the U.S. Mr. Marquez is also charged with conspiring to support terrorism.
Ms. Chernykh isn’t suspected of involvement in the attack, according to law-enforcement officials. But her case highlights the challenge to deter and identify visa overstays, those who enter the country legally and fail to leave by the stipulated date.