In societal subjects the same facts can be used to justify different conclusions. As an example, look at all the wildly different economic policies that are recommended by different economists who are all looking at the same data published by The Fed.
I know that "Alternative Facts" has a lot of vernacular baggage around it due to the crowd size fiasco with Donald Trump's inauguration. Putting that aside, an alternative fact can really just be a datapoint from a different perspective. And that's often how I see every argument. I don't use "Alternative Facts" as a synonym for lying.