The syntax looks odd to us English speakers because the initial noun phrase (una prima particolarità...), which we would expect to be the subject, is actually the object of the infinitive "cogliere" and reinforced by the pronoun "-la". The subject of the impersonal main verb "è dato" is not explicit.
For this use of "essere dato", check out:
http://www.wordreference.com/iten/non ci è dato sapere or
http://www.wordreference.com/iten/può essere datoThe phrase "una prima particolarità giuridica italiana è dato coglierla" means "it is possible to perceive a first idiosyncracy of Italian law".