The "<Lawyer Name> In Trust" is a bank account that the lawyer uses to keep clients' money. The lawyer will pay the seller from the "In Trust" account on your behalf.
I can't say there is no risk, but the risk of stealing your money by the lawyer is low. It was because if a lawyer stole your money from his/her "In Trust" bank account, he/she would lose his lawyer license and he/she would not be a lawyer in Canada/USA in the future.
In brief, it is your trust on his/her professional practice as a lawyer.