According to the normative view of science, what should scientists leave at the laboratory door?

The normative view of science is that scientists should leave their personal beliefs and agendas at the laboratory door. This means they should be unbiased, and only stick to the facts as they are presented in a scientific experiment or study.

But does this really happen?

Data show that scientists are not as unbiased as they should be. For example, in a survey of over 1500 physicists, social and personality psychologists found that the majority preferred liberal political views to conservative ones. This is despite Republicans being more friendly towards science than Democrats.

Another study showed how close-mindedness negatively impacts scientific knowledge; specifically when it comes to climate change deniers who refuse to accept evidence because their conclusion contradicts their own beliefs about human causation for global warming -despite overwhelming research pointing otherwise. In other words, bias matters whether we want it or not! Does this mean all scientists have agendas?

No: some people do excellent work without compromising objectivity by putting their personal opinions on the line while others may reserve certain ideas.