The Faculty of Advocates said current legislation on the issue was piecemeal, lacked clarity, and did not include enough measures to protect victims of the crime.
Its comments were made in response to a consultation on the Human Trafficking (Scotland) Bill being proposed by Jenny Marra, who represents North East Scotland. Human trafficking offences in Scotland fall under two separate laws - the UK Asylum and Immigration Act and the Sexual Offences (Scotland) Act.
Ms Marra believes bringing the offences into a single law and giving a new criminal definition of trafficking would make it easier to bring perpetrators to justice.
More than 90 people were trafficked into Scotland in 2011, according to figures.