Mass. Guid. Evid. 407
This section is derived from doCanto v. Ametek, Inc., 367 Mass. 776, 780 (1975), and Simmons v. Monarch Mach. Tool Co., 413 Mass. 205, 214 (1992), abrogated on other grounds by Vassallo v. Baxter Healthcare Corp., 428 Mass. 1, 20-23 (1998).
Subsection (a). Evidence of the following subsequent remedial measures has been excluded: sanding stairs or the street, Barnett v. Lynn, 433 Mass. 662, 666 n.5 (2001); National Laundry Co. v. Newton, 300 Mass. 126, 127 (1938); installation of a flashing light signal at a railroad crossing, Ladd v. New York, N.H. & H.R. Co., 335 Mass. 117, 120 (1956); repositioning a barrier across a sidewalk, Manchester v. City of Attleboro, 288 Mass. 492, 493 (1934); and precautions taken to avoid another collapse of a trench, Shinners v. Proprietors of Locks & Canals on Merrimack River, 154 Mass. 168, 169-171 (1891). The rule has been extended to exclude the results of a defendant's investigation into the causes of an accident. See Martel v. Massachusetts Bay Transp. Auth., 403 Mass. 1, 5 (1988).
Subsection (b). Evidence of a subsequent remedial measure is admissible to prove issues other than negligence. See Santos v. Chrysler Corp., 430 Mass. 198, 207-208 (1999) (manufacturer on notice of product defect); Schaeffer v. General Motors Corp., 372 Mass. 171, 175-176 (1977) (feasibility of giving adequate warnings); doCanto v. Ametek, Inc., 367 Mass. 776, 780-781 (1975) (feasibility of safety improvements); Reardon v. Country Club at Coonamessett, Inc., 353 Mass. 702, 704-705 (1968) (knowledge of the danger at time of accident); Finn v. Peters, 340 Mass. 622, 625 (1960) (ownership or control over the premises). Evidence of a preaccident remedial measure is also admissible for the same purposes. See doCanto, 367 Mass. at 780; Torre v. Harris-Seybold Co., 9 Mass. App. Ct. 660, 676 (1980).
When a party offers evidence of remedial measures to prove an issue other than negligence, the judge should determine whether it is relevant, see Section 402, General Admissibility of Relevant Evidence, and, if so, whether the probative value of the evidence is substantially outweighed by the danger of unfair prejudice, see Section 403, Excluding Relevant Evidence for Prejudice, Confusion, Waste of Time, or Other Reason. If the judge admits the evidence, the judge should, upon request, instruct the jury that the evidence cannot be considered as an admission of negligence or fault. See Section 105, Limiting Evidence That Is Not Admissible Against Other Parties or for Other Purpose; Section 403, Excluding Relevant Evidence for Prejudice, Confusion, Waste of Time, or Other Reason.