Phillip graduated from the University of Otago in 1985 with a B.A.(Hons) / LL.B. After several years at McElroy Milne in Auckland he worked in London as a commercial litigator obtaining a Masters in Corporate and Commercial Law from the University of London in 1994. Upon his return to New Zealand Phillip was a litigation partner at Grove Darlow before moving to the independent bar in 2009.