Wisconsin Legislative Council
AMENDMENT MEMO
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Memo published: March 13, 2025 Contact: Katie Bender-Olson, Principal Attorney
Abby Gorzlancyk, Staff Attorney
2025 Assembly Bill 100 Assembly Amendment 1
2025 ASSEMBLY BILL 100
Assembly Bill 100 requires school districts, independent charter schools, and private schools
participating in a parental choice program (hereinafter, “schools”) to designate all interscholastic,
intramural, or club athletic teams or sports for either males or females. The bill also requires schools to
prohibit students of the male sex from participating on a team or in a sport designated for females, and
to prohibit students of the male sex from using locker rooms designated for females.
Assembly Bill 100 also provides a cause of action for female students against a school for harm resulting
from the school’s violation of the bill, and a cause of action against a school or athletic association or
organization for retaliation or other adverse action resulting from reporting a violation.
The bill defines “sex” to mean the sex determined at birth by a physician and reflected on the birth
certificate.
ASSEMBLY AMENDMENT 1
Assembly Amendment 1 creates a definition of “biological sex,” allows schools to designate teams or
sports as coed, limits the cause of action for female students, and makes changes relating to prohibited
use of locker rooms based on sex.
First, the amendment deletes the definition of “sex” in Assembly Bill 100 and replaces it with a
definition of “biological sex.” The amendment defines biological sex to mean the physical condition of
being male or female at birth, as stated on an individual’s original birth certificate.
Second, the amendment permits a school to designate an interscholastic, intramural, or club team or
sport as either for: (1) males; (2) females; or (3) males and females. The original bill did not permit a
school to designate a sport or team as mixed-sex.
Third, the amendment eliminates the cause of action for a female student against a school or athletic
association or organization for harm arising from a violation of the prohibition on male students using
locker rooms designated for females, or arising from retaliation for reporting such a violation.
Finally, the amendment deletes the original provision relating to locker rooms, and instead, creates a
separate statute specific to the use of locker rooms. The amendment defines “locker room” to mean an
area in a school building designated for students to change clothes or be in various stages of undress
and to be used by more than one individual student at a time, and includes a shower room.
The amendment requires school boards and governing bodies of charter schools and private schools to
designate each locker room located in a school building controlled by the entity for exclusive use by
individuals of one biological sex, but creates limited exceptions. - 2 -
Pursuant to a policy, a governing body may temporarily re-designate a locker room for use by the
opposite biological sex for special events. A governing body may also allow individuals of the opposite
biological sex to enter a locker room under the following circumstances: (1) for custodial purposes; (2)
for maintenance or inspection purposes; (3) to provide medical assistance; (4) the individual is a
teacher, school administrator, police officer, or emergency services personnel performing duties related
to their employment; (5) the individual is a child being assisted by a family member or guardian; (6) to
provide assistance to an individual with a disability; (7) the locker room is temporarily designated for
exclusive use by the individual’s biological sex; or (8) during a natural disaster, emergency, serious
threat to student safety, or during a fire, tornado, or school safety drill.
A student or parent of a minor student may submit a written request for accommodations relating to
locker room use, which the governing body must provide. The accommodations may include use of a
single-occupancy locker room or the regulated use of a staff locker room.
BILL HISTORY
Assembly Amendment 1 was introduced by Representative Dittrich on March 11, 2025. On March 13,
2025, the Assembly Committee on Educated adopted the amendment and then passed the bill, as
amended, on votes of Ayes, 7; Noes 4.
For a full history of the bill, visit the Legislature’s bill history page.
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