Obama said that his administration did not ascribe motives to Russia's alleged meddling in the 2016 campaign ahead of Election Day because he did not want to be seen as influencing the outcome in favor of Democratic presidential nominee Hillary Clinton, or risk exposing the nation's electoral system to greater attack.
Speaking at a year-end news conference, Obama said, “Imagine if we had done the opposite, it would become immediately just one more political scrum,” he added.
https://www.washingtonpost.com/news/post-politics/wp/2016/12/16/obama-to-face-reporters-friday-at-his-final-year-end-news-conference/?noredirect=on
