Character plays an important role in decision making, though the people you work with and the culture you work around will affect your behavior and thus your decisions. Dr. Muel Kaptein gives a summation on this subject in his book 'Behavioral Ethics in Organizations'. The article elaborates on the five most common reasons that good judgement among teams can falter.
The article is also posted on two different websites:
bebibubo.com/what-causes-good-employees-to-make-bad-decisions-gregory-ciotti.html
www.psychologytoday.com/blog/habits-not-hacks/201411/why-do-good-employees-make-bad-decisions