The authorities which issue such licenses may fix the rate of interest which such pawnbrokers may receive on loans, and may fix different rates which may be received for different amounts of money lent; and no licensed pawnbroker shall charge or receive a greater rate of interest than that so fixed. Any such pawnbroker who violates any provision of this or the preceding section shall be punished by a fine of not more than fifty dollars.
Mass. Gen. Laws ch. 140, § 72