She was succeeded as Premier by Craig Cannonier on 18 December 2012, when she led her party into election defeat, losing her own seat in the process.

Following the General Election in November 1998, Cox was appointed the first PLP Minister of Labour, Home Affairs and Public Safety.

On 1 November 2001, Cox was given a new assignment and appointed the Minister of Education and Development and was later that year named in the Bermudians' Best of Bermuda Gold annual listing as the most effective politician for 2001.

She and her father were unique in Bermuda and party politics in both being Ministers in the first PLP administration and the only serving father-daughter duo in Parliament.

On a tip by Mikhail Fridman's Alfa Group, she investigated the financial activities of Leonid Reiman, his attorney Jeffrey Galmond, and their firms including the $1 billion Bermuda-based IPOC International Growth Fund which was competing against Alfa Group for the former share held by Leonid Rozhetskin's LV Finance in the Russian telecom giant Megafon.

[6][7] In March 2004, she hired two inspectors from the Financial Advisory Services division of KPMG to independently investigate IPOC International Growth Fund for irregularities and report the findings to the Bermund Monetary Authorities (BMA).