Dig. 9.2.9.4

Ulpianus 18 ad ed.

Sed si per lusum iaculantibus servus fuerit occisus, aquiliae locus est: sed si cum alii in campo iacularentur, servus per eum locum transierit, aquilia cessat, quia non debuit per campum iaculatorium iter intempestive facere. qui tamen data opera in eum iaculatus est, utique aquilia tenebitur:

An Aquilian action can lie if persons were throwing javelins in sport.  However, if others were throwing javelins in a field, a slave passed though it, the Aquilian action fails, since the slave should not have walked through the field for javelin throwers at that time (intempestive).  If some one threw the javelin at him, the thrower will be liable for an Aquilian action.