Justice, we are not making an empirical claim at all. Nothing in our Copyright Clause claim hangs upon the empirical assertion about impeding progress. Our only argument is, this is a structural limit necessary to assure that what would be an effectively perpetual term not be permitted under the copyright laws.
This case involves more than one party
In this case, "party" refers to the people affected legally affected by the case, not the lawyers or judges. Because, we do not know much about the nature of the case and who is involved, we cannot say definitively whether or not more than one party is involved in this case. The system may have though I was referring to the judge and the lawyer. 
( z1 involve :ARG1 ( z2 party :quant ( z3 more-than :op 1 ) ) :ARG2 ( z4 case :mod ( z5 this ) ) )