The Supreme Court announced Tuesday that it will consider whether or not United States citizenship law that favors children of unwed American mothers over those with unwed American fathers is a gender-based violation of the US Constitution's equal rights provision.

If children born abroad have unwed parents, and only one is an American citizen, current immigration law gives different treatment depending on the gender of the American parent. Despite attempts at reform, children of unwed American mothers today have an easier time gaining US citizenship than the children of American fathers.

This disparity will come before the court through the case of Luis Ramon Morales-Santana, the son of an American citizen father, who was denied American citizenship.

Under current law, American fathers are required to spend at least five years living in the United States before their children born abroad and out of wedlock are allowed to seek citizenship. (A 2012 amendment lowered the time requirement from ten years.) American women, however, are only required to prove that they have lived in the United States for one year before their children can seek citizenship.

In July 2015, the second US Court of Appeals in New York struck down the law, saying that the rule was an example of "impermissible stereotyping," and that it imposed an unfair burden on fathers. After the US Justice Department's loss at the appellate level in New York, the department took the case to the Supreme Court.

Since 2000, the US has been trying to deport Mr. Morales-Santana, who was born in 1962 in the Dominican Republic and has legally lived in the US since 1975. In 1995, he was convicted of four counts of attempted murder and two counts of robbery.

Morales-Santana’s now-deceased father missed the five year residency cut off by just twenty days, he said. His parents married in 1970. Morales-Santana argues that his father should have legally been considered a resident for the entire five year period, including his time in the Dominican Republic, since he was working for a US-owned company. In 2015, the 2nd Court of Appeals in New York rejected his four arguments for derivative citizenship.

He had also claimed, however, that the different rules for mothers' and fathers' residence in the US violated his father's right to equal protection. The court ruled that the 1952 Nationality Act’s different gender-based residency requirements did nothing to advance the government’s stated interests with the Act: avoiding statelessness and ensuring a sufficient connection between citizen children and the United States.

Critics of the 2nd Circuit Court’s decision argue that the Constitution’s Equal Protection clause should not apply to foreign citizens, saying that Congress has the right to establish any rule it wants regarding the residency requirements for US citizens and their offspring.

Conservative critics also say that this decision could be a slippery slope, leading to widespread judicial amnesty for non-citizens.

The Supreme Court will hear the case in the next cycle, and will issue a ruling before June 2017. The last time the court ruled on a similar case it came to a split 4-4 decision after justice Elena Kagan recused herself, likely because of her previous position in the Justice Department.

This report contains material from Reuters.