Traditionally, before tort reform, under established principles of joint and several liability, when the negligence of multiple tortfeasors produced a single indivisible injury, the tortfeasors were held jointly and severally liable. Watts v Smith, 375 Mich 120, 125; 134 NW2d 194 (1965); Maddux v Donaldson, 362 Mich 425, 433; 108 NW2d 33 (1961). In Watts, 375 Mich at 125, the Michigan Supreme Court, quoting Meier v Holt, 347 Mich 430, 438-439; 80 NW2d 207 (1956), observed:

In the absence of any Michigan cases on point, analogous Michigan cases in the automobile negligence area involving questions of joint liability after the simultaneous impact of vehicles and resultant injuries, are instructive. In Watts v. Smith, 375 Mich. 120, 134 N.W.2d 194, quoting Meier v. Holt, 347 Mich. 430, 80 N.W.2d 207, the Michigan Supreme Court said: "Although it is not always definitely so stated the rule seems to have become generally established that, although there is no concert of action between tort feasors, if the cumulative effects of their acts is a single indivisible injury which it cannot certainly be said would have resulted but for the concurrence of such acts, the actors are to be held liable as joint tort feasors."

Watts v. Smith, 375 Mich. 120, 125 (1965) (citing 1 Cooley on Torts, 4th Ed., § 86, pp. 279, 280). In determining whether multiple tortious acts concurrently caused an indivisible injury, the Michigan Supreme Court endorsed the view that “concurrence . . . has no reference to time, except that both torts must precede the damage.”

Traditionally, before tort reform, under established principles of joint and several liability, when the negligence of multiple tortfeasors produced a single indivisible injury, the tortfeasors were held jointly and severally liable. Watts v Smith, 375 Mich 120, 125; 134 NW2d 194 (1965); Maddux v Donaldson, 362 Mich 425, 433; 108 NW2d 33 (1961). The tort-reform statutes have replaced joint and several liability in most cases, with each tortfeasor now being liable only for the portion of the total damages that reflects that tortfeasor's percentage of fault.

The principles of joint and several liability allow multiple tortfeasors to be held liable as long as their tortious conduct produced a single, indivisible injury. See Watts v Smith, 375 Mich 120, 125; 134 NW2d 194 (1965). Here, the jury found ProMedica liable for tortious interference with a business expectancy and Leader liable for defamation, both of which led to the revocation of Dr. Byrnes's hospital privileges and resulting economic damages.

Under established principles of joint and several liability, where the negligence of two or more persons produces a single, indivisible injury, the tortfeasors are jointly and severally liable despite there being no common duty, common design, or concert of action. Watts v Smith, 375 Mich. 120, 124-125; 134 N.W.2d 194 (1965); Maddux v Donaldson, 362 Mich. 425, 433; 108 N.W.2d 33 (1961). Here, with regard to wrongful death, Community and defendants, through successive negligent acts, produced a single, indivisible injury, i.e., the death of plaintiff's decedent.

Although the highway commission could only be culpable for the latter damages under plaintiff's theory of the accident because of the indivisible quality of plaintiffs injuries, had the commission been found liable, its liability would have been joint and several with that of Ms. Robbins for the entire damages. See, e.g., Watts v Smith, 375 Mich. 120, 125; 134 N.W.2d 194 (1965), Maddux v Donaldson, 362 Mich. 425; 108 N.W.2d 33 (1961). "Proximate cause" has been defined as "`that which in a natural and continuous sequence, unbroken by any new, independent cause, produces the injury, without which such injury would not have occurred * * *'". Michigan Sugar Co, supra, 14, quoting Weissert v City of Escanaba, 298 Mich. 443, 452; 299 N.W. 139 (1941).

See, Meier v. Holt, 347 Mich. 430; 80 N.W.2d 207 (1956), DeWitt v. Gerard, 281 Mich. 676; 275 N.W. 729 (1937), DeWitt v Gerard, 274 Mich. 299; 264 N.W. 379 (1936), Frye v. Detroit, 256 Mich. 466; 239 N.W. 886 (1932). Compare Watts v. Smith, 375 Mich. 120; 134 N.W.2d 194 (1965), Maddux v. Donaldson, 362 Mich. 425; 108 N.W.2d 33 (1961). "whether [the] liability of alleged polluters is joint or several * * *. Where the injury itself is indivisible, the judge or jury must determine whether or not it is practicable to apportion the harm among the tortfeasors.

Accord: Prosser, Law of Torts (3d ed), pp 258, 269. See Lindsay v. Acme Cement Plaster Co. (1922), 220 Mich. 367, 375; Moffit v. Endtz (1925), 232 Mich. 25; Slater v. Ianni Construction Co. (1934), 268 Mich. 492, 494; Watts v. Smith (1965), 375 Mich. 120, 125. For more such usage, see Restatement, Torts (1939), § 885, Comment, p 462: "At present persons whose independent tortious conduct contribute to a tort are in most cases (see § 879) regarded as joint tortfeasors without distinction between such persons and those who co-operate in producing a tortious result."

Where it is impossible to determine which one of several tortfeasors was responsible for an injury, a plaintiff can join them all in one action and let them fight out liability among themselves. See Watts v. Smith, 375 Mich. 120, 134 N.W.2d 194 (1966); Maddux v. Donaldson, 362 Mich. 425, 108 N.W.2d 33 (1961); Schindler v. Standard Oil Co., 166 Ohio St. 391, 143 N.E.2d 133 (1957); Maryland Cas. Co. v.Frederick Co., 142 Ohio St. 605, 53 N.E.2d 795 (1944); Cuddy v. Horn, 46 Mich. 596, 109 N.W. 32 (1881). The theoretical basis for joint and several liability is the same as that for vicarious liability generally — it is fair under some circumstances to enhance the recovery possibilities of an injured victim even at the risk of making a possibly innocent party pay the cost.