In parallel with her parliamentary activities, Lotriet was DA Provincial Chairperson in the Free State between September 2012 and November 2020.

After unsuccessful campaigns for higher leadership in 2018 and 2020, she was elected to deputise Helen Zille as Deputy Chairperson of the DA Federal Council in April 2023.

[4] Between 1985 and 1994, Lotriet was a lecturer in the education department at Vista University in Bloemfontein, the capital of the Free State.

[10] She also represented the DA in the ad hoc constitutional review committee established by Parliament to debate land expropriation without compensation.

[13][14] In the interim, and while still holding her Free State role, she launched an unsuccessful bid to enter the party's national leadership, standing for election as the DA's federal chairperson in 2018.

[17] Pursuant to the May 2019 general election, Lotriet was one of two candidates nominated to succeed Anchen Dreyer as chairperson of the DA's parliamentary caucus.

[20] In that capacity, she served briefly as acting Leader of the Opposition in October 2019 after Mmusi Maimane's unexpected resignation from the DA.

[21] Thereafter she returned to her position as caucus chairperson in the Shadow Cabinet of John Steenhuisen, who was elected to succeed Maimane.

[24] In August 2021, the DA nominated Lotriet to serve as Speaker of the National Assembly, a position recently vacated by Thandi Modise.

On 14 June 2024, she was elected Deputy Speaker of the National Assembly of the South Africa,[31] Lotriet is the first non-ANC member to hold this position since B.G.