Interesting... question re public domain

[Mr Downtown]

He's dead wrong. Nothing newer than 1923 can be ASSUMED to be in the public domain. Some works newer than that MIGHT now be in the public domain, but rest assured that 1970s television shows owned by Paramount Pictures and still in syndication are not among them.

Here's a helpful chart about copyright expiration:
http://www.unc.edu/~unclng/public-d.htm