RIPPLE, Circuit Judge.

Joyce Robinson, a brakeman for the Burlington Northern Railroad Company ("Burlington" or "the railroad"), was injured while she was directing the switching movement of seventeen railroad cars from one track to another. She brought this action against Burlington under the Federal Employers' Liability Act, 45 U.S.C. § 51-60 ("FELA"), alleging that the railroad's negligence caused her injury. Ms. Robinson appeals from the jury's verdict for the railroad and the district court's denial of her motion for a new trial. For the following reasons, we affirm the judgement of the district court.

I [2] BACKGROUND [3] A. Facts

On a sub-zero January morning in 1994, Ms. Robinson was assigned to a yard switching job in the Cicero departure yard. As the foreperson of the switch crew, she was to oversee the movement of railroad cars from one track to another. Working with engineer Grant Hinton and brakeman Mike Aguirre as her crew, Ms. Robinson boarded the lead car, positioned herself on the ladder and directed the switching movement using a hand-held radio. Her crew, in the engine cab seventeen cars away, was approximately 900 feet from Ms. Robinson and could not see her. The engine was traveling at the normal switching speed of about 4 miles per hour as it shoved the string of rail cars slightly uphill on number 6 track for a quarter mile. The engineer testified that there was no evidence of defects in the equipment or operation of the train that day.

Each train car was coupled to another and to the engine by a connector called a knuckle that attaches to the drawbar of the next railroad car. Because of the design of the couplers, there is movement or "play" between the cars. The jerking movement associated with train starts and stops, caused by the extension and retraction of the couplers and drawbars between the cars, is called "slack" action. The amount of slack action varies according to the train's speed, the distance available for the train to stop, the terrain and grade of the track, the type of brakes on the engine and the speed with which the brakes are applied. Engineer Hinton testified that severe slack action could occur, "depending on speed and other variables," if the independent brake is applied too quickly. R.48-3 at 207-08. However, he also testified that the slack action that occurs during a switch, when the train is going only 4 miles an hour, should not be great enough to knock someone off a car. Nevertheless, it is this slack action that Ms. Robinson claims caused her to fall from the ladder of the lead car. We therefore focus on the events leading to Ms. Robinson's fall.

Once the train made the switch onto number 6 track, Ms. Robinson gave the engineer the stop signal; she testified that she had to give a second signal before the train actually stopped. After the train came to a stop, Ms. Robinson testified, she felt a normal slack action and began to dismount from the rail car. At that point, however, she testified that an abnormal, rough slack action occurred. As a result, she lost her balance; when she fell to the ground, her right ankle was injured. Ms. Robinson asserted that normal slack action would not be sufficient to cause someone to lose her grip. According to Ms. Robinson, the cause of the rough slack action was that "[e]ither the equipment wasn't working properly or the engineer stopped the train too fast." R.48-2 at 69.

Engineer Hinton's report of the circumstances at the time of Ms. Robinson's injury differed from hers. He testified that, as he was shoving the cars further up number 6 track, he lost radio communication with Ms. Robinson. Following normal procedures, therefore, Hinton coasted to a stop as he was required to do until he received further instructions. Perhaps seconds or a minute or so after the train came to a stop, he testified, Ms. Robinson told him, "Okay: Shove them my way." R.43-3 at 197. Hinton described what he did next: "And then we shoved just a very few feet, maybe a boxcar length or half a boxcar, and she said, `That'll do.' And then at that time she called Mr. Aguirre down to finish up [the job]." Id. The engineer was asked to describe his stop; he testified:

The initial stop was made basically by coasting down to a stop, because we had no communication, so I had to bring the movement to a stop. And then when we started up again, the engine only moved very, very small, very short distance, and then we stopped again. So both times would have been with the independent brake.

Id. at 197-98. Hinton expressed the opinion that the slack would not have been severe under those circumstances. Id. at 199.

Kenneth Hamlet, a switchman/brakeman and conductor with the railroad, reported that he was in an engine several tracks away from track number 6 on the morning in question. He testified that he heard, on his radio, the communication between Ms. Robinson and her crew. His testimony indicated that, after she had ordered the engineer to move the train 5 car lengths, she stated, "That'll" and then "it's like she got cut off in the middle of sentence or something." R.48-4 at 393. Hamlet testified that he "heard the crew calling her saying, `Did you say "that will do," Joyce?'" but she did not respond on the radio. Id. at 394.

Hamlet also described the view he had of the rail cars on track 6; he stated that he briefly saw Ms. Robinson as the car on which she was riding passed him on that adjacent track. Hamlet testified that Ms. Robinson was positioned on the back of the car rather than on the side ladder. He also testified that he had noticed that, when the train stopped, the stop appeared smooth and nothing indicated that there was a rough slack action. When he did not hear Ms. Robinson's response on the radio, however, Hamlet got off the engine and walked over to track 6, intending to let Ms. Robinson use his walkie-talkie to complete the move; he found her hobbling on one foot.

At trial Ms. Robinson offered another factor which may have contributed to her accident. She testified that, on that morning, she was wearing the "Iceman" boots which the railroad had provided its employees for cold weather conditions. Those boots were, according to Ms. Robinson, awkward and slippery and too wide for her feet to fit on the bottom rung, or stirrup, of the ladder. Because of those boots, she testified, her left foot slid across the rung and she lost her balance.

B. Jury Determination

This case came to trial on December 16, 1996. Ms. Robinson alleged that her injury while working on one of Burlington's trains was caused by the railroad's negligence: by an equipment malfunction, by the engineer's excessively abrupt application of the brake, by the clumsy and slippery boots provided by the railroad, or by a combination of those factors. Among the claims in her complaint and at trial was one based on the theory of res ipsa loquitur. The complaint stated:

[A]t the time and place alleged the cut of cars, the persons operating movement of the cut of cars, the throttle and braking system, and all of the appurtenances of the locomotive and cars were under the maintenance, operation and control of and in the exclusive possession of the defendant, and severe slack action occurred causing plaintiff to be thrown from the side ladder of car and to be injured, and accidents of the nature described herein do not occur in the ordinary course of operations if defendant had used ordinary care.

R.1 ¶ 8(a). Ms. Robinson proposed a res ipsa loquitur jury instruction; however, the court refused to give it.

On December 19, 1996, the jury returned a verdict in favor of the railroad. The trial court denied Ms. Robinson's motion for a new trial. This appeal was filed in timely fashion.

II [16] DISCUSSION [17] A. The Res Ipsa Loquitur Jury Instruction 1.

Ms. Robinson's claim is based upon FELA, a federal statute providing that a railroad is "liable in damages to any person suffering injury while he is employed by such carrier in such commerce . . . for such injury or death resulting in whole or in part from the negligence of any of the officers, agents, or employees of such carrier." 45 U.S.C. § 51. The Supreme Court has construed liberally this statute in order to promote the remedial goal of allowing recovery for injuries and deaths of railroad workers, in recognition of the physical dangers of such work. See Consolidated Rail Corp. v. Gottshall, 512 U.S. 532, 543 (1994). Nevertheless, the Court has made clear that the statute does not turn a railroad into the workers' insurer. "`The basis of [the employer's] liability is his negligence, not the fact that injuries occur.'" Id. (quoting Ellis v. Union Pac. R.R. Co., 329 U.S. 649, 653 (1947)).

"What constitutes negligence for the statute's purposes is a federal question, not varying in accordance with the differing conceptions of negligence applicable under state and local laws for other purposes." Urie v. Thompson, 337 U.S. 163, 174 (1949). In Urie, the Court also recognized that FELA "is founded on common-law concepts of negligence and injury, subject to such qualifications as Congress has imported into those terms." Id. at 182. In Gottshall the Court reiterated that principle. See 512 U.S. at 543. In conformity with Urie and Gottshall, we have declared that it is well settled that we treat negligence claims under FELA as federal questions. See Gillman v. Burlington N. R.R. Co., 878 F.2d 1020, 1022 (7th Cir. 1989).

The doctrine of res ipsa loquitur (a Latin phrase meaning "the matter speaks for itself") is applicable in FELA cases and, in appropriate circumstances, permits an inference of negligence on the part of the railroad for railroad-related injuries. The Supreme Court set forth the prerequisites for invoking a res ipsa loquitur claim in a FELA action in Jesionowski v. Boston Maine Railroad, 329 U.S. 452 (1947):

"[W]hen a thing which causes injury, without fault of the injured person, is shown to be under the exclusive control of the defendant, and the injury is such as in the ordinary course of things does not occur if the one having control uses proper care, it affords reasonable evidence, in the absence of an explanation, that the injury arose from the defendant's want of care."

Id. at 456 (quoting San Juan Light Transit Co. v. Requena, 224 U.S. 89, 98-99 (1912)). Following Jesionowski, other circuits have formulated more precise approaches to the doctrine's applicability. An approach that recurs in the case law of the circuits is the Fourth Circuit's formulation requiring the satisfaction of three conditions:

(1) the injury for which the plaintiff seeks recovery must be of a kind that ordinarily does not occur in the absence of negligence;

(2) the injury must have been caused by some agency or instrumentality within the exclusive control of the defendant; and (3) the injury must not have been due to any contribution or voluntary activity on the part of the plaintiff.

Stillman v. Norfolk W. Ry., 811 F.2d 834, 836-37 (4th Cir. 1987).

Another formulation of the FELA res ipsa requirement articulated by the federal courts is based on the Restatement (Second) of Torts:

[A]n inference of causation based on the res ipsa loquitur doctrine requires that (1) the event be of a kind which ordinarily does not occur in the absence of negligence, (2) other responsible causes, including conduct of the plaintiff and third persons, are sufficiently eliminated by the evidence, and (3) the indicated negligence is within the scope of the defendant's duty to the plaintiff.

Beissel v. Pittsburgh Lake Erie R.R. Co., 801 F.2d 143, 149 (3d Cir. 1986) (citing Restatement (Second) of Torts, § 328D (1965)), cert. denied, 479 U.S. 1088 (1987).

One of the most succinct expressions of the general rule was stated in Pennsylvania Railroad Co. v. Pomeroy, 239 F.2d 435 (D.C. Cir. 1956), cert. denied, 353 U.S. 950 (1957):

In general, the rule is that, where an injury occurs which in the ordinary course of things would not have occurred if the one having control had used proper care, a reasonable basis is afforded, in the absence of any explanation, to attribute the injury to the lack of care on the part of the defendant.

Id. at 446.

These formulations, although helpful to a court's analysis, must be implemented with care. In Jesionowski, which remains the governing precedent, the Supreme Court emphasized that, in the context of FELA cases, federal courts were to avoid "conceptualistic" interpretations of the res ipsa loquitur doctrine that might unduly restrict the "jury's power to draw inferences from facts." Jesionowski, 329 U.S. at 457. The Fifth Circuit, in Dugas v. Kansas City Southern Railway Lines, 473 F.2d 821 (5th Cir.), cert. denied, 414 U.S. 823 (1973), elaborated on the Supreme Court's caution. It noted that, in Jesionowski, the Supreme Court permitted the application of the doctrine even when there was some evidence that the plaintiff's participation in the employer's activity might have produced the accident. The Fifth Circuit's discussion of Jesionowski is instructive:

In that case a brakeman, while in the process of switching cars, was killed when a car was derailed, throwing him to his death. The Court of Appeals for the First Circuit had held that res ipsa loquitur could not be invoked in an extraordinary accident growing out of a set of circumstances which included activity of the injured person. Evidence on behalf of the railroad was sufficient to authorize, but not compel, a jury finding that the derailment was caused by the negligence of the deceased in handling the switch. There was other evidence from which a jury could have found that the derailment was caused by a defect in a frog operated with a spring mechanism. This was disputed by evidence to the effect that the frog and switch were in good condition both before and after the derailment.

Subsequent to a discussion of the general principles applicable to the use of res ipsa, the Supreme Court held that the rule as applied by the First Circuit

. . . would bar juries from drawing an inference of negligence on account of unusual accidents in all operations where the injured person had himself participated in the operations, even though it was proved that his operations of the things under his control did not cause the accident. This viewpoint [un]duly restricts the power of juries to decide questions of fact, and in this case the jury's right to draw inferences from evidence and the sufficiency of that evidence to support a verdict are Federal questions. A conceptualistic interpretation of res ipsa loquitur has never been used by this Court to reduce the jury's power to draw inferences from facts. Such an interpretation unduly narrows the doctrine as this Court has applied it.

Dugas, 473 F.2d at 824-25 (quoting Jesionowski, 329 U.S. at 457).

In short, the Supreme Court took the view that a jury can be instructed first to determine whether the plaintiff's conduct was a contributing factor to the accident. If the jury finds that the plaintiff's conduct did not contribute to the accident, it then can employ the doctrine of res ipsa loquitur to determine whether the accident was caused by the employer. Later, however, the Supreme Court emphasized that this approach was designed for the situation in which it was clear that the occurrence, absent the possible negligence of the plaintiff, was extraordinary in nature, not a usual happening, and therefore subject to the inference that it "occurred as a result of negligence." Herdman v. Pennsylvania R.R. Co., 352 U.S. 518, 520 (1957). "The rule deals only with permissible inferences from unexplained events." Johnson v. United States, 333 U.S. 46, 49 (1948).

2.

We now apply these general principles to the record before us.

Ms. Robinson contended at trial that her injury was caused by the abnormally severe slack action that occurred while she was riding on the ladder of the lead railroad car. She claimed that such rough slack does not occur without either equipment failure or mishandling by a railroad employee and that, as a result, her injury was caused by the negligence of the railroad. Having presented sufficient evidence to support this theory of the case, she submits, the jury should have been given a res ipsa loquitur instruction. According to Ms. Robinson, the trial court's refusal to give her requested res ipsa jury instruction was prejudicial, not harmless, error.

When a trial court refuses to give a proposed jury instruction, we review the allegedly erroneous omission of that instruction "with an eye towards the adequacy of the instructions actually given." Kovacich v. Benjamin, 951 F.2d 114, 116 (7th Cir. 1991). Our role in considering jury instruction challenges is limited. See E.E.O.C. v. AIC Sec. Investigations, Ltd., 55 F.3d 1276, 1283 (7th Cir. 1995). "The submission of inadequate jury instructions requires reversal only if `it appears that the jury's comprehension of the issues was so misguided that one of the parties was prejudiced.'" Soller v. Moore, 84 F.3d 964, 969 (7th Cir. 1996) (quoting In re CLDC Management Corp., 72 F.3d 1347, 1353 (7th Cir.) (citations omitted), cert. denied, 117 S. Ct. 166 (1996)). To make that determination, we evaluate the jury instructions altogether, as a whole, for their sufficiency in informing the jury correctly of the applicable law.

Our examination of the record in this case reveals that there was an instruction about severe slack action; the jury was instructed that "plaintiff claims that the defendant was negligent because defendant failed to manage and control its train to avoid excessive slack action." R.48-4 at 480. Therefore Ms. Robinson's theory of the case was placed before the jury. See United Airlines, Inc. v. United States, 111 F.3d 551, 555 (7th Cir. 1997) (affirming that district court's rejection of instruction did not deprive jury of statement of critical element in the government's theory of the case); Kovacich, 951 F.2d at 116 ("If the substance of the tendered instruction is sufficiently covered by other instructions, the refusal of such an instruction will not ordinarily constitute error."). In addition, we note that the jury heard extensive details about this central claim during Ms. Robinson's opening and closing statements and in the witnesses' testimony. The jury was well apprised of her theory of the case.

Nor can we conclude that the proposed instruction correctly stated the law of res ipsa loquitur in FELA cases as mandated by the Supreme Court in Jesionowski. It did not require the jury to conclude that the cause of her injury had to be under the defendant's exclusive control and that she, the injured person, had been without fault in the matter.

Finally, we believe that Ms. Robinson's submission must fail because there was evidence before the jury that permitted its members to conclude that her injury was due to negligence on her part and that the railroad was not negligent. Res ipsa does not apply when the accident could have occurred in the absence of the defendant's negligence. In this case, there was evidence before the jury that Ms. Robinson had positioned herself on the back of the car on which she was riding rather than on the side, the correct position. There was also evidence that there was no unusual slack action as the train came to a stop. Therefore the accident could have occurred without any negligence on the part of the railroad.

B. Denial of Motion for a New Trial

Ms. Robinson also argued to the district court that the jury verdict was against the manifest weight of the evidence and that the trial court should have granted her motion for a new trial. "The district court may grant a new trial `only where the verdict is against the clear weight of the evidence, and we will reverse the district judge's decision only where there is a clear abuse of discretion.'" Trzcinski v. American Cas. Co., 953 F.2d 307, 315 (7th Cir. 1992) (quoting M.T. Bonk Co. v. Milton Bradley Co., 945 F.2d 1404, 1407 (7th Cir. 1991)). As long as there is a reasonable basis in the record to support it, we will not overturn a jury's verdict.

In this case, Ms. Robinson was the only witness who testified that the railroad was negligent. The inconsistencies between her testimony and the testimony of other witnesses allowed the jury to parse the facts, to weigh the credibility of each witness and to disregard the testimony it found less credible or incredible. This role of fact assessing and credibility weighing is clearly within the province of the jury. After our review of the evidence, we agree that there is a reasonable basis in the record for the jury verdict. See Maier v. Lucent Techs., Inc., 120 F.3d 730, 738 (7th Cir. 1997). The district court did not abuse its discretion by denying the motion for a new trial.

Conclusion

For the reasons we have discussed above, we affirm the judgement of the district court.

AFFIRMED