The invitation was well-received and designed to educate.

Seattle city councilmember Lisa Herbold asked State Sen. Mark Miloscia if he wanted to visit Vancouver, B.C. and specifically, see North America's first supervised heroin injection site.

"When you're looking at the problems for people and neighborhoods without an approach that combines strategies in a cohesive way," said Herbold, "I think the benefits of these sites are much greater."

Miloscia is an outspoken critic of the program, and said he would introduce legislation to prevent it from coming to Washington. The visit, he said, merely reinforced his point-of-view.

"I feel like this is just the first stem to medical heroin," said Miloscia, "It's leading to the decriminalization of heroin and de-stigmatization of heroin use, which will make it worse."

Vancouver is home to Insite, North America’s first supervised heroin injection site. Insite, which opened in 2003, also connects addicts to health services, including counseling, treatment, and housing.

Herbold also visited three other sites that support addicts: The Rainier Hotel, a treatment and housing program for women; Providence Health Care site of SALOME, a clinical trial for alternative chronic heroin addiction treatment; and Woodward’s, a department store turned mixed use building.

In September, a King County task force recommended opening safe injection sites to help reduce overdoses and prevent Hepatitis B, C, and HIV. The task force recommended opening two sites in a 3-year long pilot program.

Related: Heroin addicts get safe place to use under King County plan

The highly controversial proposal has drawn mixed reaction from King County residents.