I believe you are incorrect. The laws of macrophysics (mechanics) are time-symmetric. Several quantum mechanical operations have recently been proposed as non-time symmetric (such as K-meson decay). At this point, I am reaching the edge of my expertise (the last time I took a physics course... double-majored physics/math for a while... was several years before the experiments quoted), but several experiments at CERN (see this) and elsewhere have suggested that certain weak force interactions violate charge and parity invariances, which means they must have an equal-sized time variance to balance out the CP violations, in order to remain CPT invariant.
Either way, both CPT invariance and time invariance tend to be premises in order to hypothesize further, as opposed to confirmed fundamental laws. But universal time invariance is most certainly not accepted to the point of saying that "the laws of physics are time symmetric" ...
You selected the macroscopic example of a ball falling, not me.
--Boris