Sex between educators and students, regardless of age, would be banned under a bill endorsed Friday by the Montana Senate. 

The Montana Senate unanimously endorsed HB 173 on Friday, less than a month after it passed the House.  

The bill was amended in the Senate Judiciary committee, making it less rigid and compatible with a similar bill the appears likely to become law. Because it was amended, it will head back to the House before it can advance to Gov. Steve Bullock's desk. 

The original version of the bill, sponsored by Rep. Shane Morigeau, a Missoula Democrat, instituted a blanket ban on sex between students and school employees and volunteers. 

A separate proposal sponsored by Kalispell Republican Sen. Keith Regier, SB 132, included scenarios in which a sexual relationship would be allowed, like if two students continued dating after one graduated, and the graduate became a volunteer coach at 19 while dating the 17-year-old student.

Now, both bills have exclusions only for marriages. 

In Morigeau's bill, the definition of who's affected was also subtly loosened. The original version defined perpetrators as "a school employee, school volunteer, or an independent contractor who works directly with students."

That was changed to a perpetrator who "is not a student ... and is an employee, contractor, or volunteer of any school who has ever had instructional, supervisory, disciplinary, or other authority over the student in a school setting."

Regier's bill adopted similar language through an amendment in the House Judiciary Committee. 

That bill also includes a provision that would bar school employees from helping someone convicted under the new law, if adopted, to obtain employment. 

The bills received support from the Department of Justice and several education advocates. Superintendent of Public Instruction Elsie Arntzen supported Regier's bill. 

However, The Montana Public Education Center, an organization with ties to school boards, administrators, the teachers' union and other advocacy groups, expressed "reluctant opposition."

The group advocated for a one-year "cooling off" period during which students would still be off-limits for a year after graduating or dropping out or within a year of a teacher resigning or being fired. The provision would be aimed at preventing "grooming" scenarios.  

In Montana, the Office of Public Instruction is tasked with investigating conduct that may cause a teacher or administrator to lose his or her license, including "immoral conduct." The Board of Public Education, a board of governor appointees, hears cases and rules on them. 

But if students are older than Montana's 16-year-old age of consent, there's no criminal teeth in the rulings.

It's unclear how many such cases there are, but they appear to be rare, at least when it comes to public disclosure. 

In November 2018, a Ronan middle school teacher had his license revoked after the Office of Public Instruction and Board of Public Education concluded he had an inappropriate sexual relationship with an 18-year-old high school student. 

During the past five years, only one other teacher had his or her license revoked, in that case for falsifying documents used to obtain licensure. There has been one license suspension for immoral conduct, and five license surrenders during that period. Most of those cases have been during the past two years, according to the Office of Public Instruction.