Tiana Hawkins, 32, left, of Clinton, Md., and Annissia Hawkins, 32, of Temple Hills, Md., say they both wanted to attend a Mother’s Day tea party at their son’s school. (Sarah L. Voisin/The Washington Post)

The instructions on the invitation for the Mother’s Day tea party were explicit. “One (1) Mother or Mother Figure per child.”

Annissia Hawkins and her ex-wife, Tiana, were stunned.

They tried to give National Christian Academy, the Maryland private school their son had attended for three years, the benefit of the doubt. After all, they said, the teachers and other parents were always welcoming. But they couldn’t help wondering whether their “same-gender loving family” was being singled out.

School Principal Andrew C. Stewart told The Washington Post that the limit was based on cost and space and was necessary because aunts and grandmothers of other students at the school in Fort Washington also wanted to attend.

But Annissia Hawkins said she and Tiana got a different explanation when they met with Stewart: that allowing two mothers to attend was not a stance he was willing to take because of the school’s religious beliefs.

The principal denied Hawkins’s accusation.

The Maryland State House in Annapolis. (Bill O’Leary/The Washington Post)

Now the Prince George’s County family’s experience is being cited in Annapolis as proof of the need to strengthen anti-discrimination laws for private schools that receive state funding.

The ACLU of Maryland is pushing for passage of a bill that would allow private schools to be sued over alleged discrimination, an option that now exists only for public schools under Maryland law.

Similar legislation has failed in the General Assembly for the past three years.

Civil liberties groups say they have grown increasingly concerned about protections for private school students and their families at a time when Gov. Larry Hogan (R), the Trump administration and some state lawmakers in Maryland and across the country are pushing to direct more public money to private schools.

Proponents of the bill are largely focusing on schools that participate in Broadening Options and Opportunities for Students Today (BOOST), a three-year-old program that provides state-funded scholarships to low-income students. Hogan’s proposed budget for next year includes $10 million for BOOST, up from $7 million this year.

The legislation would also apply to private schools that receive state grant money for textbooks, computers and safety measures.

The law that created BOOST scholarships prohibits private schools from discriminating against applicants based on race, color, national origin or sexual orientation, but it does not allow schools to be sued for discrimination. If a school violates the rules, it must return the scholarship money and could be removed from the program.

Schools that receive BOOST funds sign a “letter of assurance” that they will not discriminate in accepting students, but state law does not address discrimination after enrollment.

The proposed legislation would prohibit schools that receive state money from refusing enrollment, expelling or withholding privileges from a student or prospective student because of a person’s race, color, religion, sex, age, national origin, marital status, sexual orientation, gender identity or disability. If a school discriminates, it would have to return state money and could be subject to a lawsuit.

Opponents of the bill say sufficient anti-discrimination protections are already in place under federal law and the BOOST budget language. The Maryland Catholic Conference said it is not aware of any other state program in the country that goes as far as the proposed bill suggests. But the ACLU of Maryland says the protections are sorely needed.

“Our office hears from families often who have been subject to discrimination by schools who receive BOOST funding,” said ACLU public policy director Toni Holness. “The only recourse the school faces is that they lose their funding. There is no remedy for the teacher, the family or the student who is discriminated against.”

According to legislative analysts, one Lutheran school in Harford County that receives BOOST funding had to return money because its handbook said the school reserved the right to deny admission to gay and transgender students.

There was lively debate over the bill in a House committee session last week but no clear sign of whether it has a better chance of passage.

House Speaker Michael E. Busch (D-Anne Arundel), an ardent public school supporter who reluctantly voted to create the BOOST program as part of a budget compromise, sat in on the debate even though he is not on the committee.

The bill, which was also discussed in a Senate committee, would need to be approved by at least one chamber by March 18 to have a strong chance of passage.

Tiana and Annissia Hawkins said they contacted the ACLU after talking to Stewart and other parents at National Christian Academy, which receives BOOST funding, and filing a complaint with the BOOST advisory board.

Tiana Hawkins said she was willing to pay to cover the cost of having a second mom attend the Mother’s Day event. She also checked on the capacity of the site where the tea was held and learned that it could accommodate more than 80 people. There were 25 children in the prekindergarten and kindergarten classes.

Stewart said collecting money from the Hawkinses would not have solved the issue. “If it was offered to them to pay then I would have had to open it up for the rest of the parents,” he said.

In an email to the principal, Tiana Hawkins wrote: “I do not understand why a limit of only one mother would be necessary for a party that is supposedly in celebration of mothers. . . . The prohibition of additional mothers seems quite targeted to my family.”