After a stint as trial attorney for the Internal Revenue Service, Vasquez became a partner in the law firm of Leighton, Hood and Vasquez from 1982–87, and had a private practice as a tax lawyer in San Antonio from 1987-1995. He was appointed by President Bill Clinton as Judge, United States Tax Court, on May 1, 1995, for a term ending April 30, 2010. On August 5, 2010, Judge Vasquez was nominated for reappointment by President Barack Obama, but the United States Senate failed to act on the nomination. Vasquez entered senior status on May 1, 2010, and remained on senior status while awaiting Senate confirmation of his nomination for reappointment. President Obama resubmitted the nomination on January 26, 2011. Vasquez was reconfirmed on October 13, 2011, for a term ending October 12, 2026.