When a graduate school applicant chooses to take the GRE, GMAT, or LSAT, the decision is primarily determined by the type of program he or she wishes to enter. The GMAT is used for admission to most MBA or Master's of Business Administration programs. While there are some MBA programs that do allow applicants to submit GRE scores in lieu of the GMAT, it is still the preferred test format. LSAT is used for admission to law schools, while the GRE is used for admission to all other types of graduate study.
The GMAT tests quantitative, verbal and analytical writing skills. While it is more similar to the GRE than the LSAT, the GMAT is considered to cover more difficult subject matter than the GRE. The test covers critical reasoning, sentence completion, reading comprehension and contains a more comprehensive math section. In contrast, the LSAT focuses primarily on logical reasoning, analytical reasoning, reading comprehension and writing. The LSAT is more a test of an individual's thinking and reasoning skills than a general knowledge or I.Q.
If a potential graduate student seeks admission to a law school program that is not combined with an MBA, then the LSAT is the only acceptable standardized test choice. At the time of writing, no law school programs had considered either the GMAT or the GRE as an acceptable form of standardized testing as part of their application process. To gain admission to a JD (Juris Doctor) only program, applicants will need to submit official LSAT scores as part of the process.
Law programs that do accept the GMAT are typically JD/MBA dual concentrations, which lead to a law degree and an MBA. Examples include Northwestern University located in Chicago, Illinois, and American University - Washington College of Law. American University - Washington College of Law will accept either the LSAT or the GMAT for its JD/MBA dual degree program. However, it is important to note that most, if not all JD/MBA dual concentration programs typically require a separate application process for each degree awarding department. Each department will usually require two sets of standardized test scores - one from the GMAT and one from the LSAT.