"We know there is tremendous violence and vulnerability associated with prostitution. Prostitutes are predominately victims.
"They have very much in some cases run out of options before entering this particular pursuit and with that in mind, our focus is going to be on protecting the vulnerable," said MacKay, speaking to reporters Monday outside an event marking National Victims of Crime Awareness Week.
Canada's top court struck down three prostitution laws in December and gave the federal government one year to draft something new.
Since then, the Department of Justice launched and completed online consultations with the public. It also asked Canadian police for input. CBC News has reported that, even among Canada's chiefs of police, there is little consensus on how to regulate the sex trade.
"There's an enormous range of opinion and that has again been instructive in trying to find the right balance. We are very much tasked with threading a needle here," said MacKay Monday.
MacKay added that his department has examined several regulatory regimes outside Canada, including the so-called Nordic model, which has been touted by many groups.
In Sweden, Iceland and Norway, selling sex is legal but purchasing it is not. Police in those jurisdictions focus their attention on the activities of pimps and johns.
But MacKay described the forthcoming bill as a uniquely Canadian solution.
"There is no simple answer to a question as complex as prostitution.
"Suffice it to say that we are focusing - and will be focusing in this legislation - on not only acting in the best interests of the vulnerable and Canadians, but also there will need to be support mechanisms outside the legislation in order to help people to transition out of the sex trade," MacKay said.