Final answer:
The Supreme Court would likely apply an intermediate standard of review to a law that discriminates based on gender, requiring the government to show that such treatment is substantially related to an important governmental objective.
Step-by-step explanation:
The Supreme Court would most likely apply an intermediate standard of review to determine whether a policy that discriminates based on gender is an unconstitutional violation of the equal protection clause. Discrimination based on gender or sex is generally examined with intermediate scrutiny, as established by the Supreme Court in cases such as Craig v. Boren (1976) and Clark v. Jeter (1988). This level of scrutiny requires the government to demonstrate that the gender-based differential treatment is substantially related to an important governmental objective.
In contrast, laws that discriminate based on race, religion, or national origin are subject to strict scrutiny, the highest standard of review, where the government must show a compelling state interest, and the law must be narrowly tailored to meet that interest using the least restrictive means. The rational basis test is typically applied to other forms of discrimination not based on sex, race, ethnicity, or religion, such as age or disability, unless the characteristic in question is part of a suspect or quasi-suspect class.