Goldsmith was born in 1971 in the Auckland suburb of Mount Eden to parents Lawrence, a mathematics teacher, and Margaret, a palliative care nurse.

[5][8] After a year, he moved to working for John Banks, then the National Party minister of local government, as a press secretary and speech writer.

[7] The biographies were criticised in 2021 by labour historian Ross Webb as "hagiographies" of those involved in New Zealand's economic reforms in the 1980s and 1990s.

[12] Goldsmith successfully stood for the Auckland City Council Hobson Ward at the 2007 local body elections as a member of Citizens & Ratepayers.

[13] He was appointed deputy finance chairman by Mayor John Banks and chaired the community services committee.

[24] Following the March 2018 National Party portfolio reshuffle, Goldsmith became spokesperson for revenue and economic and regional development.

[28][24] Stuff.co.nz writer Thomas Coughlan described him as "possibly the most libertarian or right-wing person to hold the shadow finance portfolio.

Goldsmith argued that the Government needed to take action in response to a 51% increase in gang membership (over 3,000 individuals) over the past five years.

Goldsmith's decision drew criticism from Federation of Islamic Associations of New Zealand (FIANZ) President Abdur Razzaq, who argued that there needed to be limits to free speech when it crossed the lines into defamation and incitement of violence and hatred.

[45] On 26 June, Goldsmith confirmed that the Government would encourage judges to hand down "cumulative" sentences for offences committed on parole, bail or in custody.

Earlier, the National-led Government had announced it would require "cumulative" sentences for such offenses but backtracked due to concerns about increasing the prison population.

[47] On 15 July, Goldsmith in his capacity as Justice Minister signed an extradition order against fugitive Internet millionaire Kim Dotcom.

Dotcom had spent the past 12 years fighting against extradition to the United States where he is facing several charges of copyright infringement, money laundering and racketeering related to his Megaupload website.

[48] On 10 November, Goldsmith confirmed that the Government would introduce new anti-stalking legislation with new restraining and harmful digital communications orders, and prison terms for stalking.

[49] On 14 November, Goldsmith introduced new legislation that criminalised covert and other subversive activities on behalf of a foreign power "to intentionally or recklessly harm New Zealand.

"[50] On 21 November, Goldsmith confirmed the Government would introduce legislation to give sexual abuse victims the power to decide whether convicted offenders should receive name suppression.

[56] In June 2021, Goldsmith attracted controversy for stating that colonisation had been "on balance" good for Māori because it had led to the creation of New Zealand.