[4] Winkelmann began work as a law clerk with Auckland firm Nicholson Gribbin (later Phillips Fox, now DLA Piper).

The objective of that List was to enable proceedings flowing out of the Christchurch earthquake to be dealt with promptly and in a time frame that met the needs of the community.

She held roles as the chief justice's representative on the Council of Law Reporting, and the Chair of the Institute of Judicial Studies.

[9] On 17 December 2018, it was announced that Winkelmann would succeed Dame Sian Elias as Chief Justice,[3] and she was sworn in on 14 March 2019,[10] becoming the second woman to hold the office.

In the 2019 Special Honours, in preparation for her taking up the role of Chief Justice, Winkelmann was appointed a Dame Grand Companion of the New Zealand Order of Merit.

[11] An important role of the Chief Justice is Administrator of the Government, when the Governor-General is unable to perform their duties (due to a vacancy in the position, illness, absence from New Zealand or some other cause).