I personally think the most severe one is biasness. With enough said, the biggest thing about it to me is that it can really affect a great deal in small or big affairs. With it, it could influence and implant ideas or viewpoints that highlight a certain party's better side. This could especially be a great deal in presidential elections. It would affect the entire country or even the world and cause a great deal of damage if the journalist's bias party did something disastrous.