It's the very same as what the minister was saying before about section 1 of the charter. What is reasonable in a free and democratic society? That has evolved over time with jurisprudence. It is an objective standard cast in subjective terms. The laws follow them--the reasonable person test and the public interest test.
It just means that a body independent of government will weigh all the factors, pro and con disclosure, and decide what is in the public interest.