On the Use of a Modified Refrain from "The Orange and the Green"

Question

I would like to use in a new song a modified version of the refrain:

Oh, it is the biggest mix-up that you have ever seen.

My father, he was orange and me mother, she was green.

My refrain is not exactly the above, but close enough, so that many I'm sure will get the connection between it and the refrain of the Celtic song, "The Orange and the Green."

The rest of the lyrics will be entirely different.

Moreover, the melody will be the same as that of The Orange and the Green, which, unless my ears deceive me, is the melody of "The Rising of the Moon" which dates back to the 19th century; and so, there should not, I expect, be any copyright violation on my part by using it.

Now, back to the lyrics:

I have tried to find out when and where the modern lyrics (those which make use the above refrain) may have been copyrighted, but the most I have come up with is that "The song was written by Anthony Murphy of Liverpool"; see https://en.wikipedia.org/wiki/The_Orange_and_the_Green

I can't seem to find out anything else; e.g., when the song (lyrics, I presume) were composed, and where they were first published---U.K., Ireland, or perhaps, someplace else.

Duration of copyright is different in the U.K. from that of Ireland.

I am under the impression that in the U.K., 50 years from the year in which the sound recording was made is the duration of a song's copyright. It can last for 70 years if it were published and/or made available to the public.

In Ireland, generally speaking, the copyright expires 70 years after the death of the author.

So, without knowing when and where the above refrain first publicly appeared, or who Anthony Murphy of Liverpool is or was---

QUESTION: May I make use of a slightly modified version of the above refrain in a new song, using the underlying melody, The Rising of the Moon, in a song yet to be written and first performed (I expect) in the United States?

If the answer is No, then what may I do to find out who's permission I need in order to use a refrain slightly modified from the above?

Answer 1

The Song and the Author

and the refrain of the Celtic song,...

Let's stop there a second. The orange and the Green is not a celtic song as in the premodern history celts. It is a modern song written an irishman living in England, so modern copyrights apply. The date of its author's death is relevant, not the genre of "folk" or even "celtic folk".

Written before 1965, Anthony "Tony" Murphy is credited with the song's text. According to some Liverpoolians, the song was performed by Audie in "the Washhouse" in or around 1965, at least a little before the first recording by "The Spinners". He's also on video performing the same song in what might be the "Walton Labour Club" in the same year.

In 2000 he was reported as 65 and well alive, publishing a poem book. Later posts claim he passed on 8th June 2017, followed by some obituaries.

Copyright term

The text is treated as a literary work separate from the melody (and the arrangement!). As a literary work, it is protected till 70 years after Mr. Murphy died. So, assuming his passing in 2017 was reported correctly, the 1st of January 2088 will be when the text will pass into the public domain. Before that date, any alteration to the text would require a license from the Murphy estate.

Answer 2

I am under the impression that in the U.K., 50 years from the year in which the sound recording was made is the duration of a song's copyright. It can last for 70 years if it were published and/or made available to the public.

This describes the term of copyright for a sound recording, not of a musical or literary work. The two are distinct. The words of a song are a literary work, for which the term in the UK is the life of the author plus 70 years, just as it is in Ireland.

(Oddly, Ireland's copyright term for sound recordings seems to be the inverse of the UK's: 70 years from creation or 50 years from publication.)