Data itself cannot be biased. That is a property of the human being looking at it.
However, after having learned in university that the speed of light was constant, it was precisely a look at the data itself which led to the research for Barry. He figured the data was simply being misrepresented, too.
But he has been studying it, and other data in related fields, for longer now than I think you have been alive.
In fact, you will find this quote on his home page:
It is never good science to ignore anomalous data or to eliminate a conclusion because of some presupposition. Sir Henry Dale, one-time President of the Royal Society of London, made an important comment in his retirement speech: "Science should not tolerate any lapse of precision, or neglect any anomaly, but give Nature's answers to the world humbly and with courage." To do so may not place one in the mainstream of modern science, but at least we will be searching for truth and moving ahead rather than maintaining the scientific status quo.--Barry Setterfield, March 7, 2002
It might also be noted that recent changes in several of the atomic 'constants' which must also change if 'c' is changing have been noted in the journals recently. It's not just the speed of light; the mass of the electron and Planck's constant and a few others are changing as well.
Good luck with your position -- which is the one, by the way, which is ignoring the data....