[gpm]

> The bill also invokes the notwithstanding clause in an effort to spare it from court challenges about its constitutionality.

To explain what this means, the Canadian charter of rights and freedoms (equivalent to the various rights spelled out in the American constitution) includes a clause, called the not withstanding clause, that basically says "you can make a law that violates these rights as long as you say so in the law, and you renew that law every 5 years".