A Janus faced fact would be something that has contrasting aspects. The word origin comes from Janus, the Roman two-faced god.

A Janus word is a word which is its own antonym. They are sometimes called amphibolous words, controyms, autoantonyms, contranyms or antilogies. It is a testament to the English language that context almost always eliminates the ambiguity that you think might exist with such words. Offer a Janus word with its alternate meanings, and if you like, offer a humorous use of your Janus word, or someone else's. Oversight can mean supervision over materials or processes, and it can also mean a neglectedthing or process. Presidential Oversight... Spare is another Janus word. It can mean 'over and above what is needed', or it can mean 'not abundant or plentiful'. Webster's Collegiate 1979

The word "janitor" is derived from the Roman god Janus, who was the god of doorways, transitions, and beginnings. Janus was often depicted with two faces, one looking to the past and the other to the future. The association between the word "janitor" and Janus reflects the idea of someone who oversees transitions and maintains cleanliness in a space.

January comes from the Latin word 'Janus': a Roman god.

The roman name for janus is also janus