A new study published in the Educational Researcher shows a shocking disparity in how discipline is meted out for queer girls versus their straight peers.

Girls who said they were attracted to other girls were 13% more likely to be disciplined than girls who said they were only attracted to boys. 34% of queer girls said they had been disciplined as versus 28% of straight girls.

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The study, “Sexual Orientation and School Discipline: New Evidence From a Population-Based Sample,” followed 3,394 teenagers since birth as part of the Fragile Families and Childhood Wellbeing Study.

10% of the students in the study said they were attracted to the same sex. 8% reported being attracted to both sexes, while 2% identified as gay or lesbian.

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The same disparity was not observed between male students who said they were attracted to other boys and those who said they were attracted to the opposite sex.

Author Joel Mittleman of Princeton University cautioned that the rate of boys reporting being attracted to other boys was low enough that it should “necessitate a cautious interpretation of their outcomes.”

Mittleman used the student’s sex at birth to determine sexual attraction.