As a journalist, accuracy and truthfulness is key. One of the key traits to becoming successful in this career is building up your credibility. Credibility, like trust, is very hard to gain but very easy to lose.
When you are writing a piece, rather it be someone you are going to interview or someone you are just using as an informative source you have to vet your source. Vetting your source just means to investigate them. Make sure they are accurate and truthful.
In the world we live in today, people cannot be trusted. People want attention and some people are desperate enough that they will do anything to get it. Just take Brian Williams for example.