Copyrights are often renewed so works don't go into public domain and this would be true for songs written prior to 1923.

The copyright system is a leaky sieve and mostly the idea of "intellectual property" is often misused. The root of the laws are about business. The creator wants to be paid. Here's where it gets sticky. Who is the creator? In the case of Broadway show tunes or popular music of the 30's through 60's, we would be hard-put to say that for example that Cole Porter didn't write "Night and Day". However, there is a question about "Don't Fence Me In".

Did Dylan write any of his tunes really? Did Woody, for that matter. These writer's songs can be traced directly to antecedent melodies. A.P. Carter claimed copyright for "Wildwood Flower" which he did not write. Maude Irving did years before. Did Paul Simon write "Scarborough Fair"? (the Canticle part I guess).

There are twelve notes to the chromatic scale. How original is original?

As for lyrics, I think the main issue in a court of law is proving "access" to a song that was composed by someone. If you go on BMI or ASCAP websites and check out publishing, you would be shocked at what people have claimed to have written. These copyrights, however, are really unenforceable. It can be shown that PD material was slightly rewritten and wouldn't hold water (like a sieve) in a court of law.

There was a concerted effort some time ago to put songs that are deemed traditional or folk in a Public Domain through registration with the Library of Congress. I think that this is a great idea.

I think that the copyright laws protect the established songwriters and mean little to those not well-known. The only thorn in that side is if a song is "nicked" (as the Beatles say) and it becomes famous.

Whenever a folk song can be treated as Public Domain, then the folk process survives.

Frank Hamilton