Try to get informed before speaking. Many times as a reporter I covered meetings where people would speak passionately. Then when they got it all out, they discovered they didn't have their facts straight. They were repeating what they heard from Uncle Joe, at the coffee shop or the latest tabloid. Believe all of what you know for sure, half of what you see and none of what you hear.
People exaggerate, spin, twist and downright lie.
Learn to check things out for yourself before making a decision and be ready to stand alone if necessary. Many of the most powerful changes came about in history because one person had the courage to think for himself or herself. Keep it in perspective. The stress can be tremendous and life can get pretty skewed. I think everyone would do well to work one year as a reporter someplace on the police beat.