An Ontario high school teacher who disrupted an immunization clinic and discouraged students from getting vaccinated has been found guilty of professional misconduct, the Ontario College of Teachers has ruled.

Timothy Sullivan, a veteran science teacher with the Grand Erie District School Board, described the immunization clinic as "assault and battery," while under oath at his disciplinary hearing.

The teacher said he felt "obligated to go do something about it."

The name of the Brantford-area school is under a publication ban in order to protect the identities of students.

The college has the power to revoke the certificate of a teacher found guilty of professional misconduct.

But in this case, it is proposing a reprimand and a one-month suspension of Sullivan's teaching certificate.

It's also asking that Sullivan take courses on professional boundaries, ethics and anger management.

The three-person independent discipline panel hearing the case has yet to rule on Sullivan's penalty.

Shortly after the guilty ruling, Sullivan stormed out of the hearing room and did not return.

The incident

On March 9, 2015, Sullivan entered the routine immunization clinic being held in the school cafeteria on three occasions to demand detailed information about the vaccines and, according to a witness, "shouted" at students not to get vaccinated.

During at least one visit to the clinic, he left his Grade 11 science class unattended.

Angela Swick, a registered nurse with the Haldimand-Norfolk Health Unit, told the hearing she felt "threatened and intimidated" by Sullivan.

Toronto Timothy Sullivan 2

Sullivan, seen outside the Ontario College of Teachers discipline hearing in Toronto on Tuesday, has been found guilty of professional misconduct. (Trevor Dunn/CBC)

Swick informed the school's principal, who attended the clinic and locked the doors Sullivan was using to enter the clinic. At one point, she said, another teacher was brought in to "keep an eye out for Mr. Sullivan."

After this, Swick said, she contemplated shutting down the clinic.

"We were concerned it was an unsafe environment."

The college also submitted as evidence a letter from a student who said she was scared after Sullivan told her she could die from the vaccine she was about to receive.

'Fear and concern'

"His conduct caused fear and concern," college lawyer Christine Wadsworth said in her closing arguments. "He did not act as a role model that day."

Wadsworth argued that only students' parents and doctors should be involved in the decision about a student's vaccination, not Sullivan.

"It's not a conversation that an activist teacher should take upon himself to have whenever he likes," Wadsworth said.

Sullivan, who is not a registered health professional and has no medical training, is skeptical of vaccines and argued he was trying to protect the students from them.

Teacher's defence

Sullivan said he could not afford a lawyer and represented himself with a sometimes unorganized and unorthodox defence.

"Canadians are not aware of the serious side-effects of vaccines. They're not informed. That is why I did what I did," Sullivan told the hearing in his closing arguments.

Speaking with reporters, Sullivan said he's not an "anti-vaxxer," but "pro informed consent."

Throughout the hearing, he attempted to argue that the nurses administering the vaccines at the school did not have the required "informed consent" of the students in order to perform a medical procedure.

Previous concerns

The incident at the immunization clinic was not the first trouble the school had with Sullivan regarding his beliefs about vaccines.

Brian Quistberg, the principal at the time, told the hearing he'd received multiple complaints from teachers and students about Sullivan's "anti-vaccine" views prior to the clinic.

One incident involved a student of Sullivan's giving a class presentation on the subject of vaccines.

An email Quistberg received from the student's parent, submitted as evidence at the hearing, said that Sullivan "interjected early and often" in the presentation and "argued the information was incorrect."

The email said Sullivan's "anger level escalated to the point that [the student] left the classroom in tears."

Quistberg sent a letter to Sullivan warning him about his behaviour and outlined how to deal with the issue in future.

Approximately two weeks later, the incident at the immunization clinic occurred.