In all suits now depending or hereafter to be brought in any court of law or equity by or in behalf of his Majesty, in any of his said Majesty’s territories, plantations, colonies, possessions, or dependencies, for or relating to any debt or account, his Majesty shall and may prove his debts and accounts and examine his witness or witnesses by declaration, in like manner as any subject or subjects is or are empowered or may do by this present Act.