The plaintiff was injured by falling into a trapdoor hole, located in the sidewalk of a public highway, in front of-*388a store occupied by one McMaster. On the day of the accident two of the defendant’s employees had been sent to remove from the basement of this store a load of waste paper. With the assistance of an employee of McMaster they lifted the metal trap-door, which was about three feet square, and weighed one hundred to one hundred and twenty-five pounds, and placed it against the building. After all the paper had been thrown out from the cellar, and some fifteen bundles remained on the sidewalk behind the defendant’s truck, his two employees went to a near-by store to get a drink of soda, leaving the hole unwatched and unguarded. During their absence the plaintiff, whose attention was attracted by some people who were looking at a picture in the window of McMaster’s store, stepped alongside one of them without noticing that the hole was open, and fell in. There was evidence for the jury of the plaintiff’s due care and the defendant’s negligence. French v. Boston Coal Co. 195 Mass. 334. Picquett v. Wellington-Wild Coal Co. 200 Mass. 470. Regan v. Keighley Metal Ceiling & Roofing Co. 220 Mass. 261.
The defendant introduced in evidence a “Release and Settlement of Claim,” from the plaintiff to McMaster, dated the day after the accident. There was a verdict for the plaintiff. The defendant’s exceptions are to the admission of paroi evidence of what was said to the plaintiff by the attorney in whose presence the paper was signed; also as to her intention at the time to reserve a right of action against others who might be legally responsible; to the refusal of the judge to give certain instructions requested, especially with reference to the release; and to portions of the charge on the same subject.
As matter of construction it is clear that this instrument under seal is a release, and not merely a covenant not to sue. The effect which the law attaches to a release discharging the liability of a wrongdoer is the release of other tortfeasors who are jointly liable for the injury. This rule apparently is based upon the nature of their liability, which is one and indivisible. Accordingly, if one of them is discharged, or satisfies the cause of action, there remains no foundation for an action against any one. This rule applies not only to joint torts, strictly so called, but also to cases where the negligent acts of two or more persons operate concurrently to the injury of another, so that in effect the damages *389sustained are rendered inseparable. Brown v. Cambridge, 3 Allen, 474. See Feneff v. Boston & Maine Railroad, 196 Mass. 575. In the application of this rule of law, where the release is absolute and unconditional, it must be given its full effect, and cannot be varied by paroi evidence introduced to show that the plaintiff intended to reserve whatever rights she had against this defendant. Boston Supply Co. v. Rubin, 214 Mass. 217, 221. Nor is it material whether McMaster from whom she obtained a settlement in good faith, would have been legally liable for the injury. Brown v. Cambridge, supra. Brewer v. Casey, 196 Mass. 384. This is not a case where the injured person has given to one of the joint wrongdoers a mere agreement not to sue, without discharging the cause of action. Matheson v. O’Kane, 211 Mass. 91. Johnson v. Von Scholley, 218 Mass. 454. O’Neil v. National Oil Co. 231 Mass. 20. See Connors v. Richards, 230 Mass. 436.
It is apparent from the record that the trial judge treated the release in this case as if it were a covenant not to sue. Subject to the defendant’s exceptions he permitted the plaintiff to testify that she signed the release in reliance upon a statement of the attorney that “it would let McMaster out, but I could go and do what I wanted to do with the other people;” and instructed the jury, — “if, in consequence of what the attorney said to her, she signed it, believing that she had a right of action against whoever there might be who was responsible for the injury, then it is not a bar to the responsibility of other persons.” This and the refusal to give the requests numbered 10, 14, 15, 16 and 17, constituted prejudicial error.
It is also apparent from the record that the case was not submitted to the jury on the issue of fraud on the part of the attorney inducing the plaintiff to sign the release. The judge specifically told the jury that there was nothing to indicate “conduct on the part of the attorney which induced her to refrain from reading it or to prevent her from reading it.” See Freedley v. French, 154 Mass. 339; Larsson v. Metropolitan Stock Exchange, 200 Mass. 367.
Other questions were raised by the defendant’s exceptions. Most of them are not likely to arise at another trial, and they need not be discussed.
While the other rulings asked for could not be given in the *390form requested, the first one should have been given. We do not think however that this is a proper case for ordering judgment for the defendant under G. L. c. 231, § 122. Archer v. Eldredge, 204 Mass. 323, 327.
Exceptions sustained.