Senate committee to examine census fail

A Senate committee will investigate what went wrong with the controversy-plagued 2016 census.

Labor, the Greens and several crossbenchers referred the matter for inquiry in parliament on Wednesday, with the committee to examine privacy concerns as well as reasons why the website was shut down on census night.

Government frontbencher James McGrath insisted the inquiry was unnecessary given the prime minister's cyber security adviser Alastair MacGibbon was already conducting a review.