[4] He began practising law in New Zealand in July 1860 when he joined the practice of Harry Bell Johnstone, who had started his legal firm in January 1859.

One such group, the Ratepayers' Mutual Protection Association, challenged the right of the Christchurch City Council to exist.

[7] Ratepayers started to withhold their rates, and in April 1866 the council was forced to drastically cut expenditure in order to fend off bankruptcy.

[9] A shipment of pipes that had just arrived from England was sold off, ensuring Christchurch's reputation as the most polluted and unhealthy city for another 20 years.

[8] Wynn-Williams eventually lost the lengthy case and left the Ratepayers' Mutual Protection Association, which then folded.

[10] The 10 December 1881 general election in the Heathcote electorate was contested by the incumbent James Fisher, Wynn-Williams and Major Alfred Hornbrook.

[13] Although the Christchurch newspaper The Press was conservative and thus from the opposite end of the political spectrum than Wynn-Williams, they praised him in an editorial on 21 April 1883 for speaking his forthright opinion rather than following the attitude of other politicians of saying what the voters want to hear and what is popular with them:[13] It gives us a new and a delightful sensation to read the speech he made to his constituents at Woolston on Thursday evening so free it is from humbug or deception, and so vigorous with fearless candor.His great-grandson, Robert Wynn-Williams, used the editorial as inspiration for the title of his biography.