Comment: Grammar pedantry FAIL (Score 1) 254
"This is contrary to law and sound economic policy" means ( "This is contrary to law" ) AND ( "This is sound economic policy" )
No, it doesn't. That would be written, "This is contrary to law and is sound economic policy." (More likely, it would be written, "This is contrary to law but is sound economic policy.")
When written correctly, with the Oxford Comma in place, it would have the intended meaning
There is no place for the serial (also known as "Oxford" or "Harvard") comma in that sentence, since where it is used at all, it is used in separating the final item in a series of 3 or more.
Nor would commas separating the elements do anything to tell you whether the common portion of the list ended with "is" or "to" and whether the first element started with "contrary" or was just "law".
If one was especially concerned about avoiding potential confusion of the meaning, one could rewrite the sentence as "This is contrary to both law and sound economic policy", but while that would be more explicit, it is unnecessary, but in any case throwing superfluous commas into the sentence doesn't help anything.
It is one thing to pedantic. It is something worse to be pedantic and wrong.