[6] She later completed a PhD in public policy and Political Science at University College Dublin, with a thesis entitled Institutional Change in Judicial Selection Systems: Ireland in Comparative Perspective, which won the 2015 Basil Chubb Prize for best PhD thesis at an Irish university in 2014.

[14] In December 2020, 19-year-old Fine Gael member Dylan Hutchinson dropped his campaign for a council seat after being confronted on a Dublin beach by Jennifer Carroll MacNeill about an alleged derogatory social media post he made about a previous TD.

Hutchinson was nominated as a candidate to fill a vacancy on Dún Laoghaire–Rathdown County Council after Barry Ward was elected to the Seanad in April 2020.

[25] The Phoenix has described Carroll MacNeill as fiscally conservative and being in favour of means-tested welfare payments as well as low taxes.

She regularly handed out leaflets at the popular piers in Dun Laoghaire as a message to tell women that they were not alone and to tell perpetrators that this behavior was not acceptable.

[28] Whilst Minister for European Affairs, she said Ireland recognising the State of Palestine would help move forward with the self-determination of the Palestinian people.

In a 2024 Hot Press interview she stated that she opposed the Catholic Church's "Flourish" programme for primary schools, describing its content on topics like homosexuality as offensive and inappropriate for a secular education system.

In the same interview, Carroll MacNeill strongly criticised the Catholic Church for its handling of clerical child abuse scandals, calling their actions disgraceful and their cover-ups appalling.

[31] In July 2022 Carroll MacNeill criticised the pace of the reform of sex education for primary school students, suggesting things were being deliberately "slow-walked".

[40] David Gwynn Morgan of The Irish Times said of it; "this book by an author of unusual but apt pedigree packs in a lot of new, useful information in a field crying out for it.

[41][5] She is married to former Irish rugby player Hugo MacNeill, the former managing director of Goldman Sachs Investment Banking in Ireland.