Possibly his most notable Hawke's Bay-based case was as Crown Prosecutor achieving the High Court Wellington conviction in 2002 of Jules Mikus for the 1987 killing of Napier primary schoolgirl Teresa Cormack.
While it was a case in which he did not become significantly involved until the sudden arrest almost 15 years after the tragedy, his legal career does date back to the same era of the event more than 30 years ago, starting out of Law School at Victoria University to join Langley Twigg Solicitors in Napier in 1988.
After 10 years he moved north to become a senior prosecutor with Meredith Connell in Auckland, and he started as a barrister in 2001.
After eight months as a panel member of the Auckland Crown Solicitor, he became a partner of Hawke's Bay Crown solicitors Elvidge and Partners. Seconded to the Attorney-General's Office in Samoa, for two months at the end of 2006 he returned to Hawke's Bay to practice as barrister sole.
His principal focus in the legal career has been criminal and civil litigation, and he was the convenor of the New Zealand Law Society Criminal Law sub-committee for 10 years. In 2012 he was director of the New Zealand Law Society Litigation Skills programme.
He once considered dropping out of law school for a career as a professional musician and in broadcasting, one in which he has however had a passing involvement as a commentator on some legal issues.
He also maintained interests in music and theatre, including stage productions and a mixture of efforts as a classic trumpeter, cathedral singer, and rock band bass player.
He also cycled and kayaked as part of a two-man team in last year's Coast to Coast endurance indulgence across the South Island.
Aged 56, he and wife Kathryn, an occupational therapist, have three daughters, including one practising law in Auckland and another at law school in Wellington.
He said soon after the announcement most lawyers at some stage must harbour aspirations of becoming a judge. His own appointment followed an approach from the Chief District Court Judge earlier this year, and he had to keep it secret for some time in the face of rumours circulating in the legal fraternity.
The announcement meant immediately he could no longer continue with ongoing matters, and he had to start reassigning cases, including one in court within the next 24 hours.
There's also that of Scott Watson, who was convicted in 1999 of the murders of still-missing couple Ben Smart and Olivia Hope. Krebs was involved in an application for Royal Prerogative of Mercy, currently awaiting a decision from the Governor-General on whether Watson could again appeal.