text: In December 2013, the High Court quashed a decision by O'Neill to reallocate 7% of Common Agricultural Policy funds to rural development projects that had been favoured by environmentalists. The court ruled that she was in breach of the Ministerial Code, having not sought the necessary permissions for the transfer from the Executive.
  O'Neill replaced the DUP's Simon Hamilton as Minister of Health following the 2016 election. After eight days in office, she announced she would be scrapping the lifetime ban on gay and bisexual men donating blood in Northern Ireland. On 25 October 2016, O'Neill unveiled a document titled Health and Wellbeing 2026: Delivering Together, a ten-year plan which is based on the findings of the Bengoa Report and aims to modernise the health and social care system.
  Vice President of Sinn Féin
  In January 2017, when Martin McGuinness resigned as deputy First Minister in protest against the Renewable Heat Incentive scandal, and said that he would not stand in the resulting snap election, O'Neill was chosen as Sinn Féin's new "party leader in the North". The fact that she was favoured for the leadership ahead of former IRA member Conor Murphy marked a notable break in the leadership's direct association with the organisation.