Topeka ? Nearly six years ago, social worker Teri Zenner was brutally slain while visiting a 17-year-old client.

On Thursday, Gov. Mark Parkinson signed into law a bill aimed at increasing the safety of social workers

“As a result of this legislation, lives will be saved,” Parkinson said.

Social workers will have to take six hours of safety awareness training the first time they apply to have their licenses renewed. The requirement takes effect at the start of 2011.

The measure was in response to the Aug. 17, 2004, death of Zenner, 26, who was stabbed while visiting the Johnson County home of Andrew Ellmaker, who was later convicted of murder and given a life sentence.

Zenner was a Kansas University graduate student seeking a master’s degree in social work and was working for the Johnson County Mental Health Center.

Prior to the murder, Ellmaker had been diagnosed with schizotypal, a personality disorder, and had been committed four times to a mental institution.

Matt Zenner, who had been married to Teri for about three months when she was killed, said he hoped the law would help keep social workers safe.

“Perhaps we can keep it from happening again,” he said.

Andy Mathis, Teri Zenner’s father, said, “It has been a long time coming.” He said more needs to be done to ensure the safety of social workers because many times they are trying to help people who may be prone to unexpected violence.

Sky Westerlund, executive director of the Kansas chapter of the National Association of Social Workers, said the new law is the first of its kind in the nation.

Matt Zenner and Andy Mathis said Teri Zenner loved her work. There are more than 6,000 social workers in the state.