The Massachusetts Senate overwhelmingly approved a bill Thursday to allow state residents to make a gender-neutral designation on their driver's licenses and birth certificates.
The bill, which passed by a 39-1 vote, would allow people to choose "X" rather than "M" or "F" on the state documents.
"Not everyone fits neatly into male and female," said Democratic Senate President Karen Spilka, who strongly supported the measure.
The lone vote against the bill was cast by Sen. Donald Humason, a Republican from Westfield. Humason did not speak about the legislation on the Senate floor and later declined to comment to reporters on his vote.
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The measure now moves to the House, where supporters are hopeful it will also receive a favorable nod. The Senate backed a similar proposal in the final days of the formal legislative session last year, but it did not receive final action in the House.
Under a late addition to the current bill, residents can also request to have their birth certificates amended to include a gender-neutral designation.
Such a request would require an affidavit, signed under the penalty of perjury, declaring that it was being done to reflect a gender identity and not for any fraudulent purpose. No medical documentation would be required.
"My state documents don't reflect who I am," said Katherine O'Connor, 15, a Brookline High School student who identifies as nonbinary — that is, something other than strictly male or female — and came to the Statehouse for Thursday's vote.
O'Connor, who will soon be applying for a driver's license, said listing "X" for gender would avoid confusion in the future and was "consistent with who I am and how I view myself."
Several other U.S. states and the District of Columbia authorize gender-neutral designations on driver's licenses and other forms of identification. The most recent to do so was Nevada, where the state Department of Motor Vehicles announced the new policy earlier this week.
Washington state and New York City are among jurisdictions that allow birth certificates to be amended to list "X" for gender.
The Massachusetts proposal would also apply to other forms of state identification used by people who do not have driver's licenses. An amendment sponsored by Sen. Jo Comerford, a Northampton Democrat, calls for a review of a wide range of other state forms — fishing licenses, for example — to determine if they also should reflect nonbinary gender designations.
"People know what gender they are," said Comerford. "This bill allows us to have their state documents match how they self-identify."