Boston Mayor Michele Wu said she's ready to testify before a congressional panel​ on Wednesday despite Republican lawmakers already pushing out videos that indicate questions will have an aggressive tone.

NewsCenter 5 has learned details about who was involved in the mayor's preparations for Tuesday's high-profile hearing and the attorneys hired to help.

When Mayor Wu goes to Washington, D.C, to defend Boston's status as a "sanctuary city," she will be articulating a moral argument, not a political one, argues one letter writer.