OPINION
delivered the opinion of the court,
The plaintiff railroad worker filed an action under the Federal Employers Liability Act alleging that the defendant railroad company violated its duty to provide a reasonably safe workplace during an off-site meeting by failing to anticipate that a stairway defect or debris on the stairway constituted a tripping hazard. The railroad company filed a motion for summary judgment arguing that the plaintiff was not within the scope of his employment when he fell, that he cannot prove that the railroad breached its duty under the Federal Employers Liability Act to provide a reasonably safe workplace, and that he cannot prove causation. The trial court granted the railroad cоmpany’s motion for summary judgment. The Court of Appeals reversed, holding that the trial court erred in its application of Tennessee’s summary judgment standard. We affirm the intermediate appellate court’s judgment and hold that the railroad company’s summary judgment motion fails to shift the burden of production to the plaintiff and, alternatively, that the plaintiff states a genuine issue of material fact. We remand the case to the trial court for further proceedings consistent with this opinion.
Facts
Charles D. Mills was employed as a “signal maintainer” for CSX Transportation (“CSX”), a railroad company. He and *630 other CSX employees attended mandatory safety-certification training in Cartersville, Georgia, at a Quality Inn on February 4, 2003. Mr. Mills completed a test in the early afternoon and took advantage of a twenty-five-minute break between sessions to leave the second-floor meeting room to retrieve his blood pressure medication from his truck. He used the stairs located on the outside rear of the building, which offered the quickest route to the parking lot. Mr. Mills successfully descended the upрer flight of stairs and two steps of the lower flight when he fell down the remaining three or four steps. As a result of the fall, Mr. Mills injured his head, neck, and right shoulder. Mr. Mills filed a complaint against CSX under the Federal Employers Liability Act (“FELA”) alleging that CSX negligently failed to provide a reasonably safe work place.
CSX moved for summary judgment, arguing that Mr. Mills’s fall did not occur within the scope of his employment and that he did not know what caused his fall. In support of its motion, CSX filed transcripts of two interviews of Mr. Mills conducted by CSX employees shortly after the incident and excerpts from a deposition of Mr. Mills. CSX also submitted photographs of the stairs in question taken some time after the day Mr. Mills fell. CSX argued that Mr. Mills could not identify the specific cause of his fall and that he thеrefore can only speculate as to whether he slipped, tripped, or fell for no reason.
Mr. Mills responded with the affidavit of Chris Miller, another CSX employee. In his affidavit, Mr. Miller described the stairway on which Mr. Mills fell as having an iron face and a concrete tread. The tread on the steps was slightly below the level of the face, creating a metаl lip on each stair. Mr. Miller had tripped on the same stairs as Mr. Mills but was caught by a coworker. 1 Mr. Mills argued that Mr. Miller’s affidavit, coupled with statements from the deposition and interviews in which Mr. Mills stated that he saw debris on the stairs, created genuine issues of material fact as to whether CSX breached its duty under the FELA to protect Mr. Mills from the danger and whether the lip, the debris, or both caused his fall.
The trial court granted CSX’s motion for summary judgment, reasoning that Mr. Mills offered “too many possible ways he could have fallen, and none of them which really causally can be ... connected to the actual fall.” The trial court concluded, “I don’t think he knows how he fell. I don’t think a jury will have enough evidence to know how he fell.”
The Court of Appeals rеversed, holding that CSX “failed to affirmatively negate an essential element of [Mr. Mills’s] claim or to conclusively establish an affirmative defense.” We granted CSX’s application for permission to appeal.
Analysis
The FELA, enacted by Congress in 1908, provides that “[e]very common carrier by railroad ... shall be liable in damages to any person suffering injury while he is employed by such carrier ... 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 (2006). 2
*631
A plaintiff may bring an FELA action in either federal or state court. 45 U.S.C. § 56 (2006). While federal substantive law always controls FELA claims, claims brought in state courts “are subject to state procedural rules.”
St. Louis Sw. Ry. Co. v. Dickerson,
To apply this interplay of state and federal law, we first look to federal substantive law to determine the elements of an FELA claim. An FELA claim has four elements, requiring that: (1) the employee was injured in the scope of employment; (2) the employee’s employment was in furtherance of the railroad’s interstate transportation business; (3) the railroad was negligent; and (4) the railroad’s negligence “played some рart in causing the injury for which [the employee] seeks compensation under FELA.”
Van Gorder v. Grand Trunk
W.
R.R.,
After identifying the elements of the claim, we apply Tennessee Rule of Civil Procedure 56 to evaluate whether CSX is entitled to summary judgment. To be entitled to summary judgment, CSX must show that the case presents “no genuine issue as to any material fact and that [CSX] is entitled to a judgment as a matter of law.” Tenn. R. Civ. P. 56.04. By imposing this burden of production on the moving party, Rule 56 precludes summary judgment from disposing of issues of material fact.
Cf. Steelvest, Inc. v. Scansteel Serv. Ctr., Inc.,
CSX may satisfy its burden of production by either producing evidence or referring to evidence in the record that affirmatively negates an essential element of the nonmoving party’s claim or shows that the nonmoving party cannot prove an essential element of the claim at trial.
Hannan v. Alltel Publ’g Co.,
If CSX satisfies its burden of production, we examine the evidence produced by Mr. Mills, the nonmoving party,
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to determine whether he has shown that the case presents genuine issues of material fact or that CSX is not entitled to judgment as a matter of law. In this FELA claim, we would again consult the FELA and federal eases applying the statute to answer whether any disputed facts are material. “A disputed fact is material if it must be decided in order to resolve the substantive claim or defense at which the motion is directed.”
Martin,
In its motion for summary judgment, CSX challenges three elements of Mr. Mills’s FELA claim. CSX first argues that Mr. Mills was not within the scope of his employment when he fell because he exited the meeting room using the rear stairs and was engaged in a “purely private activity” while retrieving his blood pressure medication. To support its motion, CSX argues that Mr. Mills “made the decision to use the rear exit stairs rather than using the front entrance” and that he was not in a training session when he fell.
In an FELA claim, the scope of employment includes both actual work and acts that are necessarily incidental to actual work.
Baker v. Balt. & Ohio R.R. Co.,
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CSX next argues that Mr. Mills cannot prove that CSX was negligent. We again consider federal substantive law to determine the elements of negligence under the FELA. An FELA claimant must prove the common law elements of negligence.
Consol. Rail Corp. v. Gottshall,
In support of its motion, CSX points to two interviews and a deposition of Mr. Mills in which Mr. Mills states that he was unsure what caused his fall, that gravel or small pebbles caused his fall, and that a defect on the stairs caused his fall. The record shows that Mr. Mills stated at times that he could not identify what caused his fall but that something caused his fall:
• “[A]fter I hit the ground, I didn’t know nothing much.”
• “[T]here must have been something on it, because my left foot, it just slid out from under me.”
• “I know that there was something there that causеd me to [fall].”
• “But, there had to be something there, and I don’t know what it was that caused me to fall that day.”
At other times, Mr. Mills stated that he saw debris or a possible defect on the stairs:
• “There was some loose sand or something down there, it looked like, but these steps had been worn in different places there.”
• “It was little bitty pebble like of a sandy, I don’t know, concrete mixturе or something like that.... Just a few pieces. There wasn’t four or five pieces.”
• “I looked and when I went back up these stairs, and there was some kind of little, looked like little gravel ... and I figured that might have been what I slipped on, but I was in such a state right then, I didn’t know for sure”;
• “There was something there that, maybe a round rock or something that I slipped on, made me trip.”
CSX argues that these statements show that Mr. Mills cannot state with certainty what caused his fall. CSX contends that since Mr. Mills does not know the cause of his fall on the stairway, he is unable to prove that CSX breached its non-delegable duty to provide a reasonably safe workplace.
CSX again fails to satisfy its burden of production. The record shows that Mr. Mills stated that the steps were worn and had loose sand on them. CSX’s repeated identification of Mr. Mills’s multiple statements concerning the cause of his fall does not tend to disprove that CSX breached its *634 duty under the FELA to provide a reasonably safe workplace. Nor does the variety of Mr. Mills’s statements demonstrate that Mr. Mills cannot prove that CSX breached its duty. Although Mr. Mills’s statements show uncertainty, he never contradicts the factual assertion that a stairway defect or debris on the stairway caused his fall, and he repeatedly denies that he might have fallen for no reason. CSX therefore has not satisfied its burden of production.
Finally, CSX argues that Mr. Mills cannot prove causation at trial. Under the FELA, this element requires the claimant to prove that the employer’s negligence “played any part, even the slightest, in producing the injury ... for which damages are sought.”
Rogers v. Mo. Pac. R.R. Co.,
Although the above burden-shifting analysis can be an important tool in deciding whether summary judgment is appropriate, it is not always necessary to engage in this exercise when the nonmoving party has clearly stated a genuine issue of material fact that would preclude summary judgment as a matter of law. Tenn. R. Civ. P. 56.04;
see Downs ex rel. Downs v. Bush,
Conclusion
Based on the foregoing analysis, the trial court erred in granting CSX’s motion for summary judgment because CSX neither affirmatively negated an essential element of Mr. Mills’s claim nor showed that Mr. Mills cannot prove an essential element of his claim at trial. In addition, Mr. Mills identified an issue of material fact that must be addressed to determine whether CSX breached its duty under the FELA and whether the breach, if any, caused Mr. Mills’s injuries. The existence of a genuine issue of material fact precludes summary judgment. The matter is remanded to the trial court for proceedings consistent with this opinion. The costs of this appeal are assessed against CSX Transportation, Inc., for which execution may issue if necessary.
Notes
. Although Mr. Miller's affidavit states that he tripped on February 4, 2004, a full year after Mr. Mills’s incident, the statement's context and additional references in the record indicate that Mr. Miller tripped in 2003, ”[s]hortly after” Mr. Mills.
. Tennessee’s Workers’ Compensation Law is the exclusive remedy for employees subject to that statute. Tenn.Code Ann. § 50-6-108 (2008). The statute, however, does not apply to "[a]ny common carrier doing an interstate business while engaged in interstate com *631 merce, which common carrier and the interstate business are already regulated as to employer’s liability ... by act of Congress.” Tenn-Code Ann. § 50-6-106(1)(A) (2008). CSX is a railroad company engaged in interstate commerce, and its liability for employee injuries is instеad determined by applying the FELA.
. The United States Supreme Court has held that ''[t]he weight of the evidence under the Employers' Liability Act must be more than a scintilla before the case may be properly left to the discretion of the trier of fact — in this case, the jury.”
Brady v.
S.
Ry. Co.,
. It is not entirely clear which standard of causation
Rogers
applies to FELA cases — the common law standard or a relaxed standard. In a concurrence to
Norfolk Southern Railway Co. v. Sorrell,
Justice Souter, joined by Justices Scalia and Alito, argued that the concept of a relaxed causation standard in FELA actions is incorrect and is the result of a misreading of
Rogers. Sorrell,