initially a member of the progressive conservative caucus, a rump caucus of tory senators who had refused to join the new conservative party of canada in 2003, mccoy was ultimately the last progressive conservative in the chamber following the retirement of senator lowell murray in 2011. she changed her designation to independent pc in 2013 and then to non-affiliated in 2016, following the decision by the government of justin trudeau to make the senate a non-partisan institution and appoint independent senators. in september 2016, she and 14 other non-affiliated senators formed the independent senators group to advocate for the rights of non-affiliated senators as the upper house was still organized around partisan lines resulting in non-affiliated senators being underrepresented on committees and not receiving the funding given to party caucuses. mccoy was elected facilitator of the new group for the 2016–2017 parliamentary term. in december 2016, the senate agreed to recognize the isg and granted it funding and also agreed that non-affiliated senators would be appointed to senate committees in numbers proportionate to their numbers in the senate.