GREENE, J.

We are asked to determine whether a jury instruction proposed by the plaintiff in a suit brought pursuant to the Federal Employers' Liability Act ("FELA"), 45 U.S.C. §§ 51-60 (2006), was improperly denied. Michele Collins ("Petitioner" or "Collins") brought survivorship and wrongful death actions against the National Railroad Passenger Corporation ("Respondent" or "Amtrak") alleging that Amtrak's negligence caused the death of her husband and former Amtrak employee, Robert Collins ("Decedent" or "Mr. Collins"). Mr. Collins was electrocuted while on assignment to take alignment readings of overhead electrical wires on a span of railroad track. At trial, Amtrak contended that Mr. Collins was solely responsible for his fatal injuries because he mounted the roof of a work vehicle and came into contact with an energized wire absent any specific order to do so and in violation of a company rule. At trial, Collins proposed a jury instruction explaining that Amtrak could not defend against the negligence claim by asserting that the Decedent had assumed the risks of his injury. Although FELA expressly bars the assumption of risk defense, it was injected into the trial by Amtrak; therefore, the trial judge abused his discretion by not providing a cautionary instruction.1 Accordingly, we shall reverse and remand for a new trial.

I.

On February 17, 2005, Mr. Collins was working his normal weekday shift, 10:00 p.m. to 6:00 a.m., as an Electrical Traction Lineman based out of Amtrak's Perryville, Maryland, maintenance facility. Mr. Collins had been employed in the Electrical Traction Department for approximately eight years. He was a member of a crew of five men ("the crew" or "D-126") including: the crew foreman; the Cat Car2 Operator; an Electric Traction Lineman; and an Electric Traction Lineman Trainee. Mr. Collins's job involved routine maintenance of the electrical catenary system3 along Amtrak's northeast corridor, specifically the section between Perryville and Baltimore, Maryland.

Around 3:40 a.m., the crew was directed to conduct alignment readings of the catenary system on a recently serviced section of track. The electricity remained on while the readings were taken, so the crew foreman conducted a safety briefing to discuss working under the energized wire. The readings were taken and while the crew foreman was recording the data collected during the assignment, the men witnessed a bright flash, heard an explosion, and then a thump on the roof. Mr. Boone found Mr. Collins in flames on the roof of the Cat Car. Robert Collins suffered fatal electrical burns after coming into contact with an electrified railing on the roof of the Cat Car.

It is presumed that Decedent mounted the roof of the Cat Car to manually tie down the pantograph,4 and the physical evidence indicated that Decedent sustained his fatal injuries while "stomping."5 "Stomping" was a method used by crew members of Amtrak's Mid-Atlantic South Division to communicate to Cat Car operators that the pantograph needed lowering. The "stomping" method required a crew member to climb atop the roof of the Cat Car and to stomp on the portion of the roof that was directly above the operator.6 At trial, Amtrak officials testified that a crew member had to break the company's "three-foot" rule, which requires employees to maintain three feet of distance from the catenary system, in order to use the stomping method. On cross-examination, Amtrak officials conceded awareness of the "stomping" method, but acknowledged that it did not bar the practice.

During the trial, Amtrak officials and Decedent's fellow crew members testified about Decedent's work experience, safety training, and his decision not to invoke Amtrak's Right of Refusal policy.7 Collins offered an instruction on the inapplicability of the assumption of risk defense "because of the potential overlap with assumption of risk and contributory [/] comparative negligence.... What might happen is that they could say they believe Mr. Collins was standing there, he knew that the pantograph was energized and he took, you know, the classic voluntary assuming, getting close to the pantograph to do his job."

Collins's proposed instruction No. 17 stated:

The trial judge denied Collins's proposed jury instruction. According to the trial judge, the evidence did not inject assumption of risk into the case; therefore, an assumption of risk instruction would have only confused the jury on the issue of contributory negligence. The jury returned a verdict in favor of Amtrak at the conclusion of a five-day trial.

In her subsequent appeal to the Court of Special Appeals, Petitioner contended that "there was ample evidence from which the jury could have, and most likely did, improperly draw the conclusion that [Petitioner] should not recover because [the Decedent] assumed the risk of the incident." Collins v. Nat'l R.R. Passenger Corp., 187 Md.App. 295, 307, 978 A.2d 822, 829 (Md.Ct.Spec.App.2009). Amtrak filed a conditional cross-appeal requesting that the intermediate appellate court review the Circuit Court for Baltimore City's denial of Amtrak's motion for judgment should it decide to reverse the Circuit Court's judgment. The Court of Special Appeals affirmed the judgment, agreeing that the cautionary instruction was not necessary because all of the evidence tended to implicate contributory negligence and not assumption of risk. Collins, 187 Md.App. at 315-16, 978 A.2d at 834. Collins filed a petition for a writ of certiorari in this Court and asked:

Amtrak filed a cross-petition for certiorari and presented this question:

We granted both petitions. Collins v. Nat'l R.R. Passenger Corp., 411 Md. 598, 984 A.2d 243 (2009).

We hold that a notable portion of the evidence presented by Amtrak addressed elements relevant to the defense of assumption of risk and not necessarily relevant to contributory negligence. Amtrak's evidence drew attention to the voluntary nature of Decedent's encounter with the electrified equipment and his choice to mount the roof of the train car, both of which would be ancillary to a contributory negligence analysis, which requires proof of a careless act, or failure to act, beyond knowledgeable acceptance of a dangerous condition. Thus, a cautionary instruction was necessary to instruct the jurors that they may not conclude that Mr. Collins assumed the risk of his injuries and that they were to apply the law applicable to contributory negligence only if they found first that Amtrak was negligent, and secondly that Mr. Collins's negligence contributed to his fatal injury. The error was not harmless because if the jury found that Decedent had assumed the risk of his injuries by voluntarily choosing to work under energized lines, that determination negated Amtrak's duty and operated as a complete bar to Petitioner's recovery. Further, we shall hold that the intermediate appellate court did not err in failing to reach the issue raised in Amtrak's conditional cross-appeal, because it was moot in light of that court's decision to affirm the judgment of the Circuit Court. We shall reverse the judgment of the Court of Special Appeals and direct that court to remand the case to Circuit Court for purposes of a new trial.

II.

We apply the abuse of discretion standard of review when considering a trial judge's denial of a proposed jury instruction. See Sidbury v. State, 414 Md. 180, 186, 994 A.2d 948, 951 (2010) (stating that "[t]he decision of whether to give supplemental instructions is within the sound discretion of the trial judge and will not be disturbed on appeal absent a clear abuse of discretion.") (citing Roary v. State, 385 Md. 217, 237, 867 A.2d 1095, 1106 (2005)). In Gunning v. State, 347 Md. 332, 351-52, 701 A.2d 374, 383 (1997), we reiterated that "[w]here the decision... of the trial court is a matter of discretion it will not be disturbed on review except on a clear showing of abuse of discretion, that is, discretion manifestly unreasonable, or exercised on untenable grounds, or for untenable reasons." A trial judge exercises discretion by assessing whether the evidence produced at trial warrants a particular instruction on legal principles applicable to that evidence and to the theories of the parties. Therefore, the onus is on the trial judge to discern and ensure that the jury instructions encompass the substantive law applicable to the case. While we defer to the trial judge's ruling, an improper exercise of discretion may cause prejudice to a party and result in reversible error. Cf. Flores v. Bell, 398 Md. 27, 33-34, 919 A.2d 716, 719-20 (2007) (noting that the burden is upon the complaining party to show both the probability of prejudice and error that is both "manifestly wrong and substantially injurious").

There are three requisite components to our analysis of whether the proposed instruction should have been incorporated into the ultimate charge to the jury: (1) the requested jury instruction must be a correct exposition of the law; (2) the particular law must have been applicable to the evidence before the jury; and (3) the substance of the requested instruction must not have been fairly covered by the instructions actually given. See Wegad v. Howard Street Jewelers, Inc., 326 Md. 409, 414, 605 A.2d 123, 126 (1992) (noting the impact of Maryland Rule 2-520(c) on the third component of the analysis); see Dickey v. State, 404 Md. 187, 197-98, 946 A.2d 444, 450-51 (2008) (holding the same requirements arise from the criminal law counterpart Md. Rule 4-325(c)); accord Hamrock v. Consol. Rail Corp., 151 Ill.App.3d 55, 103 Ill.Dec. 736, 501 N.E.2d 1274, 1279 (1986) (stating that "a court's charge ... will be deemed proper only where it adequately and correctly covers the substance of the requested instructions and is fair to both parties").

In Maryland, litigants are entitled to have their theory of the case presented to the jury, provided the theory is a correct exposition of the law and is supported by the evidence. Wegad, 326 Md. at 414, 605 A.2d at 126 (citing Sergeant Co. v. Pickett, 285 Md. 186, 194, 401 A.2d 651, 655 (1979)). Consequently, in a FELA case a litigant is entitled to some assurance that a defense, abolished by the governing statute, will not be considered by the jury. The use of negative instructions, i.e. instructions that the jury should `not' hinge its resolution on an inapplicable doctrine, should, however, be given only when necessary. Ellsworth v. Sherne Lingerie, Inc., 303 Md. 581, 599-600, 495 A.2d 348, 357 (1985) (indicating that judges determine when a negative instruction will be helpful and not harmful to the jury's deliberations).

In the present case, the instruction actually given by the trial judge did not reference assumption of risk nor the inapplicability of the doctrine to cases involving a FELA action.9 Our task, therefore, is to determine whether the proposed instruction was applicable to the evidence presented at trial. See also Fearnow v. Chesapeake & Potomac Tel. Co., 342 Md. 363, 385, 676 A.2d 65, 76 (1996) (stating "[i]f any one part of the test is not met, we will affirm the trial court's denial of the request for instruction"). As part of our review of the applicability of Collins's proposed instruction to the evidence, we consider the probability that the absence of the instruction impacted the jury's deliberations.

III.

Petitioner contends that Amtrak's focus on Decedent's knowledge and voluntary action in the face of a dangerous condition, rather than carelessness, implicitly appealed to the forbidden defense of assumption of risk. In response, Respondent argues that Decedent was the sole cause of his fatal injury because Amtrak gave no order to mount the roof of the car, Decedent must have known it was dangerous, and he chose to encounter the energized wire; therefore, the instruction on contributory negligence was applicable and sufficient. If, as Respondent argues, the evidence adduced at trial exclusively implicated that Decedent's fatal injury resulted from carelessly adding new dangers to conditions that the employer negligently maintained, there would have been no abuse of discretion in denying the proposed instruction. If the evidence, however, tended to show a voluntary, knowledgeable acceptance of a dangerous condition necessarily encountered to perform the duties of employment (as we perceive the record to reveal) the judge abused his discretion by denying the instruction.

Upon review of federal case law interpreting 45 U.S.C. § 54,10 the evidence adduced at trial, the jury instructions, and the verdict sheet, and in light of the applicable standard of review, we hold that there was error in omitting an instruction on the inapplicability of the assumption of risk affirmative defense and that the error prejudiced Petitioner.11

A. An Assumption of Risk Defense is Prohibited

In 1906, Congress enacted FELA, a broad remedial framework addressing recovery for injured railroad workers.12 See Atchison, Topeka & Santa Fe Ry. Co., v. Buell, 480 U.S. 557, 562, 107 S.Ct. 1410, 1414, 94 L.Ed.2d 563, 571 (1987) (explaining that Congress intended FELA to provide a remedial framework for railroad employees and to eliminate several common law defenses to tort liability); cf. Green v. River Terminal Ry. Co., 763 F.2d 805, 806 (6th Cir.1985) (noting that courts should liberally construe the provisions of FELA in favor of injured railroad employees in light of the remedial objective of the statute).

At the time of passage of FELA, the doctrine of assumption of risk was "applied generally ... because of acceptance of the theory that the employee's compensation was based upon the added risk to his position and that he could quit when he pleased." Tiller, ex. v. Atl. Coast Line R.R. Co., 318 U.S. 54, 61, 63 S.Ct. 444, 448, 87 L.Ed. 610, 614 (1943). The doctrine, however, was never practically distinct from contributory negligence and so the overlap "became the subject of endless litigation." Tiller, 318 U.S. at 63, 63 S.Ct. at 449, 87 L.Ed. at 615. In 1939, Congress abrogated the assumption of risk defense from cases brought pursuant to FELA. Petitioner extracted her proposed jury instruction for use at trial from the language of the statute:

45 U.S.C. § 54 (emphasis added); see Tiller, 318 U.S. at 58, 63 S.Ct. at 446, 87 L.Ed. at 612 (explaining that Congress intended for 45 U.S.C. § 54 to abolish every vestige of the assumption of risk defense from all claims arising under FELA). Congress abolished the doctrine of assumption of risk in the FELA cases because the doctrine failed to acknowledge that employers, not employees, controlled working conditions. See Tiller, 318 U.S. at 65, 63 S.Ct. at 450, 87 L.Ed. at 617 (noting the Senate Judiciary Committee's belief that the doctrine of assumption of risk was unsuited for contemporaneous economic activities).

Assumption of risk means, "[a]t common law an employee's voluntary, knowledgeable acceptance of a dangerous condition that is necessary for him to perform his duties...." Taylor, 787 F.2d at 1316 (citing PROSSER AND KEETON ON TORTS § 68, 480-81 (W.P. Keeton 5th ed.1984)). The effect of the amendment to FELA is that a statutory employer may no longer escape liability for deviating from the duty of care owed to employees by urging that the employee was aware of the dangers that might befall him or her but undertook employment in spite of those dangers in exchange for compensation. An employee's assumption of the risk of the employment environment is no longer presumptively implied from the terms of an employment contract and the defense may not be used to bar an employee's recovery under the Act.

FELA is a comparative negligence statute, thus, a claimant's recovery may only be reduced upon a showing of contributory negligence.13 45 U.S.C. § 53. "Contributory negligence ... is not a complete bar to a plaintiff's recovery but, rather, operates to diminish the recovery in proportion to the parties' comparative fault." Butynski v. Springfield Terminal Ry., 592 F.3d 272, 276 (1st Cir.2010) (citation omitted). "Contributory negligence... is a careless act or omission on the plaintiff's part tending to add new dangers to conditions that the employer negligently created or permitted to exist." Taylor, 787 F.2d at 1316 (citing PROSSER AND KEETON ON TORTS § 65, 451-52). Therefore, if the defendant employer in a FELA case alleges sufficient evidence that the plaintiff employee engaged in conduct that caused an undue risk of harm to himself or herself, then the jury should be instructed to apportion a percentage of fault to the employee so that any awarded damages can then be appropriately reduced. "The argument that plaintiff cannot recover because of [the] deceased's contributory negligence is wholly without merit. Contributory negligence, while it may diminish the amount of recovery, is not a [complete] defense to a cause of action bottomed on the Federal Employers' Liability Act, §§ 3, 45 U.S.C.A. §§ 53." Ramsouer v. Midland Valley R. Co., 135 F.2d 101, 107 (8th Cir.1943). Contributory negligence does not bar recovery in FELA cases, it reduces the amount of the damage award.

Despite the explicit abolition of the doctrine of assumption of risk from the resolution of claims brought pursuant to FELA, the practical complications of its similarity to contributory negligence, which is a permitted defense, persist. "[W]hen a statute exonerates a servant from [assumption of the risk], if at the same time it leaves the defense of contributory negligence still open to the master, then, unless great care be taken, the servant's rights will be sacrificed by simply charging him with assumption of risk under another name." Koshorek v. Pa. R.R. Co., 318 F.2d 364, 369 (3d Cir.1963) (citation omitted). Because a finding of contributory negligence on the part of the employee will reduce his or her damages, while a finding of assumption of risk would bar recovery, "courts [and juries] have the delicate job of separating out evidence on one theory from evidence on the other." Fashauer, 57 F.3d at 1274.

B. Determining the Necessity of a Cautionary Instruction

In our view, federal case law interpreting FELA sets a low threshold for determining whether an assumption of the risk instruction is warranted; however, there is no consensus among the federal courts as to the precise evidentiary scenarios which necessitate a cautionary instruction. The Third Circuit concluded, in Fashauer, that, "the most difficult part of the inquiry is determining when the facts merit [the instruction]." 57 F.3d at 1275. As noted by the Fashauer court, "some courts have guarded against jury confusion by ... describing assumption of the risk to the jury and instructing it not to reduce the plaintiff's recovery on that basis." Fashauer, 57 F.3d at 1274 (citing the Third Circuit's decision in Koshorek, 318 F.2d at 370 and the Ninth Circuit's decision in Jenkins, 22 F.3d at 212); see Taylor v. Burlington N. R.R. Co., 787 F.2d 1309, 1316 (1986) (holding that evidence which implicated assumption of the risk when an employee entered a hostile workplace and continued to perform his job was inadmissible altogether so no instruction was needed on how to differentiate the legal theories applicable to the evidence). Other circuits, however, have been more hesitant to provide the instruction when the doctrine is not explicitly raised by the litigants.14

In the present case, the intermediate appellate court employed the analytical approach suggested by the Fashauer court and concluded that Amtrak's evidence did not explicitly or implicitly raise the assumption of the risk defense; therefore, according to the Court of Special Appeals, the trial court committed no error in omitting the instruction. The first dispositive factor according to Fashauer is whether the employee acted pursuant to an order or to his or her own discretion. Fashauer, 57 F.3d at 1278 (recovery can never be reduced because of implied consent in performing a task as specifically directed). An employee may not be found to be contributorily negligent if he or she followed a direct order. "In other words, when a plaintiff has no real choice, his recovery should not be reduced because he performed the task, regardless of whether the plaintiff acted reasonably or unreasonably." Fashauer, 57 F.3d at 1279; accord Jenkins, 22 F.3d at 211-12. The Ninth Circuit distinguished general and direct orders in Jenkins, noting that the former implicates contributory negligence and the latter the forbidden assumption of the risk doctrine:

Jenkins, 22 F.3d at 211 (emphasis added). Under Fashauer and Jenkins, direct orders implicate assumption of the risk, while general orders implicate contributory negligence.

Secondly, under Fashauer, if there is evidence of a general order, if the employee exercised discretion, or alternative methods to perform the task were available, then the reasonableness of an employee's actions is dispositive and "unreasonable assumptions of risk constitute evidence of contributory negligence."15 Fashauer, 57 F.3d at 1278. The Third Circuit summarized the confluence of unreasonable assumption of the risk and contributory negligence as follows:

Fashauer, 57 F.3d 1269, 1276 (citing PROSSER AND KEETON ON TORTS, § 68 at 481); Smith v. Seven Springs Farm, Inc., 716 F.2d 1002, 1005 (3d Cir.1983).16

Our concern with the Court of Special Appeals's opinion, decided pursuant to Fashauer, is that it did not address the full spectrum of reasonable inferences that the jury may have drawn from the evidence regarding both orders and discretion, and reasonable or unreasonable action. We cannot say as a matter of law that the assumption of risk defense was not injected into the case because as a matter of fact it was implicated by the evidence. Thus, the jury was denied the benefit of having the law explained explicitly before rendering a verdict. Here we have "assumption of the risk masquerading under another name," and a cautionary instruction was required to ensure a proper application of the statute to the evidence presented to the jury. Green v. River Terminal Ry., 763 F.2d 805, 806 (6th Cir.1985) (explaining that in light of FELA's remedial purpose, the "statute should be liberally constructed in favor of the injured plaintiff").

Therefore, in light of the Fashauer analysis, we think it prudent for the trial judge to give a cautionary instruction when evidence of an employee's knowledge of dangerous conditions of employment is before the jury, where the jury must draw inferences from the facts about the existence of direct or general orders, and where determinations of reasonableness must be made. "[A cautionary instruction] is properly given when the issue of assumption of risk is expressly or implicitly before the jury, even though not explicitly raised at trial." Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1279. As noted by the Court of Special Appeals:

Collins, 187 Md.App. at 310, 978 A.2d at 831 (citing Fashauer, 57 F.3d at 1280) (internal citations omitted and emphasis added).

We are cognizant of the delicate task before a trial judge who must discern whether the evidence adduced might evoke an impermissible line of reasoning among the jurors, while being required under the Maryland rules of civil procedure and common law to adequately address a defendant's theory of the case, including affirmative defenses. Cf. Clark v. Pa. R.R. Co., 328 F.2d 591, 595 (2d Cir.1964) (holding that an assumption of the risk instruction "might well cause such confusion as to water down or even eliminate the issue of contributory negligence"). The potential prejudice to an injured employee, namely a complete bar to recovery, however, warrants careful scrutiny of the evidence and the inferences that jurors may reasonably draw from the presentation of the case.

C. Instruction was Applicable in the Instant Case

The jury instruction on contributory negligence was applicable to the evidence yet it was insufficient because the evidence also implicated assumption of the risk. See Siciliano v. Denver & R.G.W. R.R., 12 Utah.2d 183, 364 P.2d 413, 415 (1961), cert. denied, 368 U.S. 979, 82 S.Ct. 476, 7 L.Ed.2d 521 (1962) (noting that "[t]here may be a case where the issue was not pleaded but where the evidence so emphasizes the fact that the employee recklessly and foolishly took on a known and dangerous hazard as to `create improper inferences' that should be `dispelled' by a cautionary instruction"). In the instant case, the jury was instructed to presume that the Decedent acted with due care, i.e. that he had acted reasonably. Amtrak presented evidence about the Decedent's choice not to exercise his Right of Refusal and his failure to use the care that a reasonably prudent person would by coming into contact with the live wire, arguably, to show that the Decedent acted unreasonably. Thus, the jury was instructed about contributory negligence so that liability could be apportioned between Amtrak and the Decedent if the jury found both parties to have acted negligently.

Amtrak contended that the Decedent was the sole cause of his fatal injury because he was not acting pursuant to Amtrak's orders, he knew it was dangerous to mount the roof of the Cat Car, and he voluntarily chose to place himself at risk because he encountered an energized wire. The record reflects, and at oral argument before this Court Amtrak emphasized, that it was baffled by Decedent's choice and that the choice, in effect, precluded Amtrak's negligence under the circumstances because causation was attributable only to Decedent. An employer may not, however, benefit from a finding of non-negligence based on an impermissible inference by the jury, which is our perception of the result in this case.

The Court of Special Appeals analyzed two potential evidentiary sources of confusion for the jury, at Collins's behest, namely the Right of Refusal Policy and Decedent's decision to mount the roof of the Cat Car. That court held that there was no error in denying Collins's proposed jury instruction because neither evidentiary source necessitated an assumption of the risk instruction. Collins, 187 Md.App. at 314-16, 978 A.2d at 833-34. The intermediate appellate court explained:

Collins, 187 Md.App. at 315-16, 978 A.2d at 834. In essence, the court held that because there was no direct order to mount the roof, Mr. Collins was charged with acting reasonably, which he did not do, therefore the jury was only confronted with the possibility that he was contributorily negligent.

We conclude, by contrast, that there was evidence adduced that Mr. Collins was acting pursuant to custom, it was to be presumed that he acted reasonably, and Amtrak mounted a defense directed to the elements of assumption of the risk in addition to, if not to the near exclusion of, contributory negligence. See Joyce v. Atlantic Richfield Co., 651 F.2d 676, 683 (10th Cir.1981) (holding that, under the Jones Act applying principles of FELA, an assumption of the risk instruction was necessary because the evidence focused on the employee's acceptance of the dangerous condition and not the employee's negligent act or omission); see also Rivera v. Farrell Lines, Inc., 474 F.2d 255, 257-58 (2d Cir. 1973) (stating that a jury finding of contributory negligence based on the employee's "strength of knowledge that a dangerous condition in his line of duty ... his working in that line of duty" was "assumption of the risk masquerading under another name"). A cautionary or clarifying instruction was needed to direct the jury to consider Decedent's carelessness, not his acceptance of risk.17

1. Evidence of the Right of Refusal Policy Injected the Doctrine into the Case

Petitioner asserts that evidence of the Decedent's decision not to invoke his Right of Refusal warranted the cautionary instruction because the jury may have concluded that the Decedent assumed the risks of his employment because he did not refuse to perform the job under the particular conditions, i.e. the energized line. Respondent asserts that the evidence of the Decedent's decision not to opt out of the assignment, or request that the electricity be shut down from the area of track involved is evidence of contributory negligence, not assumption of risk because the evidence shows that safer alternatives, besides quitting, were available.

It is undisputed that employees of Amtrak may invoke the Right of Refusal policy, which was offered into evidence through the testimony of Gerard Nangle, the Director of Electrical Traction Maintenance. According to Mr. Nangle, "any member of the engineering department ha[d] the right to refuse work that they [felt was] unsafe." The intermediate appellate court held that evidence describing Amtrak's Right of Refusal policy did not "expressly or implicitly inject[ ] assumption of the risk into the trial." Collins, 187 Md.App. at 314, 978 A.2d at 833. The court's reasoning on that point follows:

Collins, 187 Md.App. at 313, 978 A.2d at 833 (first emphasis added). The intermediate appellate court concluded that Amtrak did not offer the evidence of the policy for the purpose of supporting a forbidden defense. In our view, however, it is not purpose, but the impact of the evidence and argument of counsel on the fact finder that was and is at issue.19 See Jenkins v. Union Pac. R. Co., 22 F.3d 206, 212 (9th Cir.1994) (noting "[i]t is the evidence itself, not the defendant's characterization of it, that drives the analysis"). The intermediate appellate court agreed with Respondent that evidence of the Decedent's decision that the work could be completed safely under energized wires demonstrated contributory negligence because it showed that safer alternatives, besides quitting, were available to Mr. Collins, and that he acted unreasonably in not pursing them. To the contrary, the jury could have found that the same evidence was suggestive of Mr. Collins's knowing acceptance of a danger that relieved Amtrak of its duty, thereby appealing to assumption of the risk. See Vandaveer v. Norfolk & W.R. Co., 78 Ill.App.2d 186, 222 N.E.2d 897 (1966) (ruling that evidence of an employee's ability to request another job, could have led a jury to infer that the employee assumed the risks associated with her current job and so an instruction was not improper). It is the potential impact on the jury, and not the proffered, or subsequently divined, purpose of the evidence that should govern whether a cautionary instruction is given.

Respondent's argument and the Court of Special Appeals's analysis are not persuasive because both fashion an under inclusive net to catch the instances where an assumption of the risk instruction is needed. Testimony solicited by Respondent from Mr. Nangle immediately after he summarized the Right of Refusal policy, focused on the Decedent's knowledge of policy, the extent of the safety briefing just prior to executing the assignment, and the "decision of the crew" to do the job under energized wire. The juxtaposition of the evidence of the `opt-out' policy with the repeated testimony related to Mr. Collins's knowledge and experience in his particular line of work evokes elements of the assumption of the risk defense and not careless deviation from the standard of care.

The Court of Special Appeals's consideration of the Right of Refusal Policy and that court's conclusion that it could not have raised an impermissible inference of assumption of the risk is also inconsistent with its holding in a similar case, CSX Transp., Inc. v. Richard Bickerstaff, et al., 187 Md.App. 187, 978 A.2d 760 (2009), in which a cautionary instruction was given and upheld on appeal.20 In Bickerstaff, the Court of Special Appeals identified evidence presented at trial by the appellant employer that supported the trial judge's decision to give a cautionary instruction, namely "making choices to work at a particular rail yard, to mount and dismount moving equipment at a particular speed, [and] to take on a job involving more walking...." The court concluded:

Bickerstaff, 187 Md.App. at 228, 978 A.2d at 784 (emphasis added). In the instant case, the Court of Special Appeals went beyond the evidence of the Right of Refusal policy to divine a purpose for which that evidence was offered and then to declare that purpose to be wholly in alignment with the railroad management's proffered reason for offering the evidence, namely to bolster a contributory negligence defense. The intermediate appellate court was satisfied in Bickerstaff, however, that evidence of choice of work site, analogous to the choice to work under an energized line despite recourse to the Right of Refusal Policy, was sufficient to warrant a clarifying, cautionary instruction. The Court of Special Appeals offered no persuasive reason in the instant case to distinguish its conclusion here from the one reached in Bickerstaff.

In the present case, the Court of Special Appeals also held that the evidence presented at trial regarding the reasons and presumptions about why decedent went onto the roof of the Cat Car, "tended to show that the Decedent departed from the standard of care and acted unreasonably under the circumstances, thus implicating the defense of contributory negligence and not assumption of the risk." Collins, 187 Md.App. at 315, 978 A.2d at 834 (citation omitted). In its closing statement to the jury, Amtrak highlighted Mr. Collins's knowledge of the dangers of the energized catenary system and his choice to mount the roof to tie down the pantograph. This argument, however, is consistent with the theory of assumption of risk.

In light of the conflicting evidence, it is unclear whether the Decedent was acting with the discretion that is central to the intermediate appellate court's reasoning and conclusion that assumption of the risk was not implicated. It is unknown exactly why Collins went on the roof, but physical evidence suggests he was in a position to stomp on the car roof thereby alerting the operator that he was tying-down the pantograph. The jury necessarily was confronted with conflicting evidence on precisely why the power remained on in this particular circumstance, especially in light of repeated testimony that this kind of routine maintenance was performed under a de-energized line 99% of the time. Petitioner elicited testimony at trial tending to cast Amtrak as directing the crew explicitly, through a "conscious decision," to work under an energized line. Respondent, however, contends that it was the "crew's decision" to do the alignment reading under energized wire. One of the crew members, George Breader, testified that it was the crew foreman, Thomas Boone, who made the decision to do the reading under an energized line, and the crew agreed with that decision. At trial, an Amtrak official testified that an advantage to keeping the power on was that "when you remove power, trains won't run on certain areas." One of the crew members also testified that "[t]he advantage [to keeping the power on] is that the less people that have to be involved[,] ... the less time that it requires." A reasonable jury could have inferred from this evidence that Amtrak directed Mr. Collins to `accept a dangerous condition' of employment and that there was a benefit to the company in leaving the power on during the assignment.

According to the Tenth Circuit, "when the evidence could support either contributory negligence or assumption of the risk, instructions which only define contributory negligence are not sufficient to prevent the jury from applying assumption of the risk." Sauer v. Burlington Northern R.R. Co., 106 F.3d 1490, 1493 (10th Cir.1996) (involving a FELA case where the instruction did address assumption of the risk and its inapplicability, albeit without mentioning the defense by name); see e.g., Norfolk S. Ry. Co. v. Thomas, 258 Va. 516, 522 S.E.2d 620 (1999) (noting that the same evidence may be relevant to both defenses). Here, Amtrak's theory of the case was that Mr. Collins elected to encounter the known risks of working in the vicinity of an energized wire. The jury could have concluded that Mr. Collins was carrying out continuing orders from Amtrak to tie down the pantograph as a matter of course. This interpretation of the evidence could have led to a finding of contributory negligence or assumption of risk.

2. Evidence of Custom Implicates Assumption of Risk

The Court of Special Appeals concluded, "it is clear that the evidence adduced does not show that the Decedent impliedly consented to `perform[ ] a task in the manner which [Amtrak] directed.'" Collins, 187 Md.App. at 313, 978 A.2d at 833 (quoting Fashauer, 57 F.3d at 1279-80). In our view, it is not clear that the evidence only permitted one inference, which in the intermediate appellate court's opinion, would be the inference that Decedent acted under a `general' order implicating only contributory negligence and not assumption of the risk. The jury may have reasonably inferred that the custom of tying-down the pantograph amounted to or derived from the existence of a direct order. In either case, it was a determination properly made by the jury and requiring full disclosure of the difference between contributory negligence and assumption of the risk.

Although neither party produced evidence of an explicit order to mount the Cat Car and tie down the pantograph, that was precisely what was customarily done when an alignment job was completed. Tying down the pantograph was the universally understood custom among members of the D-126 crew and it was known to Amtrak officials who did not definitively stop the practice. At trial, Amtrak's attorney asked Gerard Nangle:

Mr. Nangle answered, "No, no one, to our knowledge, gave instruction for him to go up." Thomas Boone, the crew foreman, however, offered contradictory testimony that there was a general instruction to always tie down the pantograph.

Further, Mr. Boone testified that he did not know whether the rule applied when the wires were energized or de-energized. Later at trial, Walter Foura, a Senior Project Officer in the Mid-Atlantic Division testified that he verbally communicated to foremen and supervisors to pass down to their subordinates the rule that the pantograph was to be tied down, but only under a de-energized line. In response to a question about why none of Amtrak's ground crews seemed to know about this caveat to the rule, that it be tied down under de-energized lines, Mr. Foura said that it was the responsibility of the foreman and supervisors to disseminate the information. Then, Mr. Foura testified about a 2004 memo written by upper level management explicitly stating that the pantograph was never to be tied down under any circumstance. Evidence was also adduced at trial that the crews tied down the pantograph routinely because a latch on the Cat Car which should have functioned to keep the pantograph secured to the roof of the vehicle did not function at the time of Decedent's fatal injury, and had never functioned properly. Thus, the evidence on this subject was contradictory.

It is conceivable, in light of this evidence, that the jury may have inferred that Collins was following his employer's direction that the pantograph should be tied down at the end of an alignment reading job in accordance with his understanding of his position on the crew and the customary procedure. This inference would invoke the "direct order" that, under Fashauer, warrants a cautionary instruction. This evidence about the tie down procedure, along with evidence of the safety meeting prior to the job and the investigative report finding that the Decedent acted without orders to mount the roof and approach live wire, directs attention to Decedent's knowledge, choice, and awareness of risk. The jury may have dismissed Amtrak's characterization and testimony about the custom and rules relating to tying-down the pantograph. Because we cannot know whether the jury properly considered only those aspects of the evidence relative to carelessness, we cannot be confident that the verdict reflects the jury's conclusion that the sole cause of the Decedent's injury was his own carelessness or that it was his assumption of the risk. See Jenkins, 22 F.3d 206, 211-12 (9th Cir.1994) (noting the assumption of the risk instruction is warranted if the evidence can prove either contributory negligence or assumption of the risk).

Hamrock v. Consol. Rail Corp., 151 Ill.App.3d 55, 103 Ill.Dec. 736, 501 N.E.2d 1274 (1986) illustrates how an appellate court in Illinois resolved a case where it was unclear if the employee was acting under direct or general orders. In Hamrock, the conductor "informed" Hamrock's crew about the movements that would need to be made to align the train cars in the desired configuration, and each member was to decide how to execute his part of the job. Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1276. The court said:

Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1280. In Hamrock, the court determined "defendant's attempt to show that the sole cause of plaintiff's injury was his own carelessness by emphasizing plaintiff's years as a brakeman, his familiarity with the coupling maneuver, and his knowledge of the condition of the yard underscore[d] the need for a cautionary instruction ...." Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1280. Amtrak presented a similar case here—evidence was adduced regarding Collins's training, knowledge of the procedures, and awareness of the dangerousness of working under energized lines.

The case is instructive because Mr. Hamrock, like Mr. Collins, "was familiar with the railroad's safety rules but stated that he and other train men customarily rode moving cars and manipulated the angle cock with their feet." Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1276 (emphasis added). This practice, like tying-down the pantographs, was not in accordance with the formal rules set by the employer. The court in Hamrock also stated that just because an employee violates a safety rule, that does not establish that the employee was the sole cause of his injuries "particularly in light of evidence that the rules were seldom utilized or were nullified by custom." Hamrock, 103 Ill.Dec. 736, 501 N.E.2d at 1280. Because the jury could have made the inference that Collins was on the roof of the Cat Car, to do what he understood his job to be, even under dangerous conditions, the cautionary instruction about assumption of the risk should have been given.

3. Petitioner was Harmed by the Omission of a Cautionary Instruction

Respondent contended at oral argument that Petitioner's question before this Court is moot because the jury answered "No" to "Question 1" on the verdict sheet, asserting, as we understand it, that because the jury found that Amtrak was not negligent it necessarily did not perform any analysis of proposed, or implied affirmative defenses.21 Respondent's argument fails to recognize that the structure of "Question 1" on the verdict sheet compounded the trial court's error in not instructing the jury on the inapplicability of the assumption of the risk defense. In answering "No" to the first question, the jury may have concluded that the employee had assumed the risks of his employment, thereby negating Amtrak's duty entirely, or the jury could have found that Amtrak was negligent but did not cause Mr. Collins's fatal injury because, as Amtrak characterized it, he was "solely responsible" for his injury.

A prima facie case of negligence under FELA is based on the common law elements in accordance with federal law: duty, breach, foreseeability, and causation.22,23 Szekeres v. CSX Transp., Inc., 617 F.3d 424 (6th Cir.2010) (citing Adams v. CSX Transp., Inc., 899 F.2d 536, 539 (6th Cir.1990) (holding that a FELA plaintiff asserting a cause of negligence against his or her employer must "prove the traditional common law elements of negligence: duty, breach, foreseeability, and causation")). Ordinarily the general concept of negligence and the instruction on causation, distinct elements in a negligence claim, are explained and represented in separate questions on the verdict sheet. Vol. ♥—Ch. 9, Modern Federal Jury Instructions —Civil, ¶ 6.2-6.4 (Matthew Bender 2010) (illustrating a model verdict sheet in which the elements of negligence and causation are addressed separately and in that order); see also 9-49 BENDER'S FEDERAL PRACTICE FORMS Form No. 49:34 (2010) (providing a sample verdict sheet in which the question of negligence preceded the question of causation); see MARYLAND CIVIL PATTERN JURY INSTRUCTIONS §§ 19-1, 19-10 (Maryland Bar Association, 4th ed.2009 Supp.) (defining the general concept of negligence and causation elements respectively).

The issue raised in the petition for certiorari is not moot. In the present case, negligence and causation were combined into the first question on the verdict sheet. Here, the evidence presented focused on knowledge of danger and voluntary encounter of risks. In addition, the lack of a cautionary instruction, compounded by a verdict sheet that did not separate negligence from causation, suggests that the jury may have impermissibly concluded that Mr. Collins assumed the risk of his injuries thereby negating Amtrak's duty.

We look to the jury instructions that were given at trial to determine whether they are relevant in light of the issues raised and the evidence presented.24 Jurors are presumed to have followed the instructions provided to them by the court, "[o]ur legal system necessarily proceeds upon" that presumption. State v. Moulden, 292 Md. 666, 678, 441 A.2d 699, 705 (1982) (citing Blanchfield v. Dennis, 292 Md. 319, 438 A.2d 1330 (1982)). This presumption directs our attention to the substance of the instruction, which is critically important in determining if the jury may have relied upon the defense that Mr. Collins assumed the risk of his injury.

After discussing the elements to be considered in determining if Amtrak was negligent, the trial judge instructed the jury to presume that Mr. Collins had acted with due care, i.e. that he had acted reasonably, because he was deceased and could not present testimony on his own behalf. The jury was then instructed about the law with regard to contributory negligence:

(Emphasis added.)

While the instruction given adequately covered the law applicable to negligence and contributory negligence, it failed as a matter of law because, in substance, it did not address all of the evidence and the reasonable inferences to be drawn from the evidence. Assumption of the risk is a "distinctive kind of contributory negligence," and so a jury should be instructed in a way that removes this theory from consideration. See generally PROSSER AND KEETON ON TORTS, § 68, 495. Because the instruction, particularly the language emphasized above, invokes a voluntary choice, the jury should have also been instructed to consider evidence of Decedent's carelessness independently of Decedent's knowing encounter with a danger in the course of his employment. As instructed, the elements of assumption of the risk were entangled with the elements of negligence and contributory negligence. "In working out the distinction, the courts have arrived at the conclusion that assumption of risk is a matter of knowledge of the danger and intelligent acquiescence in it, while contributory negligence is a matter of some fault or departure from the standard of reasonable conduct, however unwilling or protesting the plaintiff may be." Koshorek, 318 F.2d at 367; see Johnson v. Erie R.R. Co., 236 F.2d 352, 355 (2d Cir.1956) (holding that only instructing on contributory negligence allowed for the jury to consider assumption of the risk in rendering its verdict).

As a result of the instructions given, it is uncertain whether the jury found Amtrak to be not negligent or whether the jury's response to "Question 1" meant that the jury found Amtrak to be negligent, but its negligence played no role in causing Collins's injuries. This uncertainty is pivotal because the Circuit Court's failure to instruct on the inapplicability of assumption of the risk allowed the jurors, on the issue of causation, to consider that Collins knew of the risk of working under energized wires, and, therefore, assumed the consequences of his voluntary choice to encounter that risk. The jury, in merely considering the element of causation, may have been misled by the evidence tending to show that Decedent assumed the risk of his own injuries.

IV.

In response to Amtrak's cross-petition in the instant case, we hold that the intermediate appellate court did not err in declining to reach the issue presented in Amtrak's conditional cross-appeal, which requested the Court of Special Appeals to review the trial court's denial of Amtrak's renewed motion for judgment at the close of all the evidence. The intermediate appellate court affirmed the judgment of the trial court ruling that, in light of the evidence, Collins's proposed instruction was unnecessary. Hence, Amtrak won the appeal. Thus, the issue presented in Amtrak's cross-appeal was rendered moot by the intermediate appellate court's decision to affirm the judgment of the trial court. See Hagerstown Reproductive Health Services v. Fritz, 295 Md. 268, 272, 454 A.2d 846, 848 (1983) (holding that courts rarely review the merits of a moot case); cf. City of Frederick v. Pickett, 392 Md. 411, 424, 897 A.2d 228, 235 (2006) (noting that an appellate court "could affirm ... `on any ground adequately shown by the record, whether or not relied upon by the trial court'") (quoting Berman v. Karvounis, 308 Md. 259, 263, 518 A.2d 726, 728 (1987)). Accordingly, we hold that the Court of Special Appeals did not err in declining to address, on the merits, the issue raised in Respondent's conditional cross-appeal.

The effect of our judgment in this case is a remand for a new trial in conformance with this opinion. Because we hold that the trial judge erred in not giving Collins's requested jury instruction, we need not determine whether the trial court correctly denied Amtrak's motion for judgment.

V.

In this case, the evidence tended to show Decedent's knowledgeable, voluntary encounter with the energized equipment aboard the Cat Car, a dangerous condition of his work environment, while executing customary duties as a member of the D-126 crew. Consequently, the jury may have relieved Amtrak of liability by finding that the Decedent was the sole cause of his fatal injury because he assumed the risks involved in performing a dangerous job. Therefore, the trial judge erred in failing to give a cautionary instruction to clarify that only negligence and contributory negligence were applicable to the case. Petitioner was prejudiced because a finding of contributory negligence would have resulted in apportionment of damages, but a finding of contributory negligence disguised as assumption of the risk would result in a complete bar to recovery.

JUDGMENT OF THE COURT OF SPECIAL APPEALS REVERSED. CASE REMANDED TO THAT COURT WITH INSTRUCTIONS TO REMAND THE CASE TO THE CIRCUIT COURT FOR BALTIMORE CITY FOR A NEW TRIAL. RESPONDENT TO PAY THE COSTS.

BATTAGLIA, J., dissents.

BATTAGLIA, J., dissenting.

For the reasons presented by the Court of Special Appeals, I would affirm the judgment. Our colleagues on the intermediate appellate court properly determined that none of the evidence presented to the jury expressly or implicitly inserted assumption of risk into the trial. Based on the facts of this case, the evidence regarding the Right of Refusal and the decedent's choice to mount the roof of the train car suggested reasonable alternatives, "`besides quitting or refusing to perform the task in an unsafe way,'" Collins v. Nat'l R.R. Passenger Corp., 187 Md.App. 295, 313, 315, 978 A.2d 822, 833, 834 (2009), quoting Fashauer v. N.J. Transit Rail Operations, Inc., 57 F.3d 1269, 1280 (3d Cir. 1995), such that only the defense of contributory negligence was in issue.