In a precedent-setting case, a Vancouver hotel worker is being tried in Canada for alleged sex crimes involving child prostitution committed in another country.

A preliminary inquiry opened Tuesday in the case of Donald Bakker, 40, who faces 12 counts of sex crimes against women from Vancouver's Downtown Eastside.

Bakker, who sat in court beside his lawyer, pleaded not guilty to all 28 charges and has requested trial by judge and jury.

Donald Bakker (file photo)

Following his arrest, police said they found 70 videotapes in Bakker's home allegedly containing disturbing visuals, some of which included Asian children.

Bakker has also been charged with another 16 sex crimes which allegedly took place in another country that cannot be named because of a court ordered publication ban.

Canada's so-called sex tourism law was introduced to protect children by punishing those who sexually abuse children, including those who use child prostitutes, while outside Canada. It allows the Crown to prosecute Canadians at home for sex crimes allegedly committed abroad.

Rosalind Prober, of the lobby group Beyond Borders which pressed Canada to adopt the law, said it's about time it was put to use.

"This is the ugliest underbelly of child sexual exploitation that there is around the world," she said.

Bakker's lawyer, Kevin McCullough, said while Canadians would agree sex with children is abhorrent, Canada has no right to impose its laws on people while they are in another country.

He said that violates the basic principles of international law.

"When Canada starts to say it can police other countries in any form, in my view that sets off a problem in international relations, it offends charter rights and it offends the way Canada ought to be behaving."