Copyright laws prevents release of historic jazz recordings

No logic to this. New creations should assume Creative Commons by default and if you want copyright, then you'd have to spend some cash on it.

1930s an audio engineer named William Savory (above) made a lot of high-quality recordings of live jazz performances of Louis Armstrong, Billie Holiday, Benny Goodman, Count Basie, Teddy Wilson, Lester Young, Bunny Berigan, Coleman Hawkins and others. The National Jazz Museum in Harlem acquired the collection after Savory died.

via. Boing Boing