и.м.х.о. ясно написано - нет, нельзя.
"Children up to 1.5 m in height must always be placed in an approved restraint system or seated in a child seat suitable for their weight. Children over 1.5 m in height must wear ordinary adult seat belts. The driver, or the adult accompanying the minor, is responsible for compliance regarding the use of an appropriate restraint system/child seat or seat belts.
FINE for non-compliance (article 172, paragraph 10, Italian Highway Code): 80 to 323 Euros. PENALTY POINTS on driving licence: -5 out of 20 full starting points."
http://www.aci.it/...