From within an article at politico about possible plagiarism by Jared Keller:
It’s the latest rough patch for Keller, who has had a tumultuous couple of years. In 2013 he was fired from Bloomberg after Matthew Keys, a former deputy social-media editor at Reuters, tweeted direct messages in which Keller disparaged his employer ("I f--king hate it here," he wrote). Keller then went to Al Jazeera America, where he was the victim of a round of layoffs that took place last year. He joined Mic in April of 2014.
Yes, tweets get back to your employer. But also there is an issue of NLRA's section 7 rights.
The copying incidents were reported by gawker; politico noted a possible stress factor
One Mic.com insider notes that the incidents Gawker found happened in the last few months when the news team lost several writers and Keller began handling the news desk nearly entirely on his own.
One recalls Senator John Walsh initially invoked a stress factor impacting him at the War College in Carlisle. That invocation did not work out well for the now-former senator.