Massachusetts employers take note: The state’s Transgender Equal Rights Bill, signed into law by Gov. Deval L. Patrick on Nov. 23, 2011, went into effect on July 1.

Massachusetts is the 16th state, along with Washington, D.C., to offer transgendered individuals protection from bias, although the Massachusetts Commission Against Discrimination has taken the position for some time now that transgendered individuals are protected under the definition of “sex” as a protected class.

The law prohibits discrimination on the basis of gender identity in employment, as well as housing, credit and education.

Massachusetts’ existing anti-discrimination law, Chapter 151B, now includes “gender identity” as a protected category. Chapter 151B applies to public employers and private employers with six or more employees.

The statute defines “gender identity” as: “a person’s gender-related identity, appearance or behavior, whether or not that gender-related identity, appearance or behavior is different from that traditionally associated with the person’s physiology or assigned sex at birth.”

In addition to protecting individuals who have undergone sex reassignment surgery or are otherwise seeking care or treatment of their gender-related identity, the law also protects individuals who have a sincerely held belief that their gender identity is different from that received at birth. The law does not provide any insight into what characteristics of an individual’s identity are “gender-related.”

Employers of transgendered employees should be prepared to respond to requests to use a different name, to deviate from a company uniform or grooming policy, or to use the restroom of the non-biological sex of the employee.

In one of the few cases addressing the bathroom issue in the country, the Minnesota Supreme Court held that an employer’s designation of employee restroom use based on biological gender was lawful, even though state law prohibited discrimination in employment against transgendered employees. Goins v. West Group, 635 N.W.2d 717 (Minn. 2001).

Advocacy groups such as the Human Rights Campaign recommend that employers “[p]ermit an employee to use sex-segregated facilities that correspond to his/her full-time gender presentation, regardless of what stage that person is in terms of his/her overall transition process.”

The Transgender Equal Rights Bill does not require that. However, when employers of transgendered employees are presented with the sensitive “restroom question,” a careful legal and practical analysis must be undertaken. Employers should evaluate possible solutions that would make everyone comfortable: the transgendered employee, coworkers, and even customers.

All Massachusetts employers should update their policies, handbooks and harassment training to reflect the additional protected category of transgendered status, if they have not already.

Employers should also consider training managers about how to respond to the sensitive questions that could arise about gender identity in the workplace.

Katharine A. Crawford practices at Fisher & Phillips in Boston.