In December 2015, the Democratic National Committee suspended the campaign's access to its voter data, following the firing of a Sanders campaign staffer who allegedly viewed data from the campaign of Hillary Clinton as the result of a firewall failure, which he denies. The Sanders campaign criticized the move as an excessive reaction stemming from the inappropriate actions of a single staffer and threatened possible legal action unless the Democratic National Committee restores its access. The Sanders campaign claims it warned the DNC about glitches in the voter file program months ago. On December 18, 2015, the campaign filed a lawsuit, stating the Committee had unfairly suspended its access. Former Obama Advisor David Axelrod contended on Twitter that the DNC was "putting finger on the scale" for Hillary. The DNC and the Sanders campaign struck a deal the same day that restored the campaign's access to voter data.