BOSTON (AP) — Boston's Museum of Fine Arts has hired an outside law firm to investigate reports that a group of minority middle school students was subjected to racism by staff and patrons during a school field trip last month.

Museum leadership in a statement Wednesday said the review would be led by former Massachusetts Attorney General Scott Harshbarger of Casner & Edwards LLC.

The museum conducted its own investigation, which led to two patrons being banned for alleged disparaging remarks during the May 16 visit.

But the museum said "we came to the decision that an investigation by an external party could provide greater objectivity and clarity."

The principal of the Helen Y. Davis Leadership Academy in the city's Dorchester neighborhood said museum security followed his students while leaving white students alone.