In October 2011, during a shadow ministerial reshuffle, McKinnell was made shadow children's minister, shadowing Tim Loughton. In that post she criticised the adoption process as too slow and called for immediate improvements in support for social workers and family courts to speed up the process.[12][13] She also accused the government of doing too little to help children for whom adoption was not suitable and following this, requested a guarantee that the government would give priority to placing children in "happy homes."[14]
In June 2012, after the resignation of Peter Hain, she was then moved to become Shadow Exchequer Secretary to the Treasury, replacing Owen Smith. McKinnell backed a campaign by ActionAid on international tax laws[15] and tabled amendments to the Budget which would have required the government to monitor the impact on developing countries of changes to so-called Controlled Foreign Companies regulations. She said, "It seems a false economy to invest ... in changes that will undermine the very progress towards which our international aid money, which increases year on year, is going".[16]
Also in June 2012, McKinnell publicly criticised Take That singer Gary Barlow following newspaper allegations of tax avoidance made against him. McKinnell agreed that Barlow should consider returning his recently awarded OBE if allegations of tax avoidance were proven "because it doesn't send out the right messages to ordinary people who are paying their fair share of tax".[17]
At the 2015 general election, McKinnell was re-elected as MP for Newcastle upon Tyne North with an increased vote share of 46.1% and an increased majority of 10,153.[18]
McKinnell has been a prominent campaigner for the Women Against State Pension Inequality campaign. In December 2015, following the acceleration of the equalisation of the State Pension Age, she argued that the acceleration has happened too quickly and left female pensioners uncertain.[21] McKinnell was also made Vice Chair of the recently established All-Party Parliamentary Group on the WASPI campaign.[22]
At the snap 2017 general election, McKinnell was again re-elected with an increased vote share of 55.4% and an increased majority of 10,349.[23][24] She was again re-elected at the 2019 general election, with a decreased vote share of 45.4% and a decreased majority of 5,765.[25]
