Duty to Preserve ECM Data: What Trucking Companies Need to Know

There is little Louisiana law regarding trucking companies’ duty to preserve Engine Control Module (“ECM”) data following a motor vehicle accident. An ECM is a computer that is attached to a truck’s engine and receives data from different sources on a truck (input data) and data from reporting events and conditions (output data). An ECM can also store data about a particular event happening in the truck, such as a sudden deceleration. In the world of trucking litigation, ECM data is often used to show events that occurred surrounding an accident.

Here is what trucking companies need to know about preserving ECM data.

What is spoliation?

To determine whether there is a duty to preserve ECM data, we must first discuss spoliation, which refers to the intentional destruction of evidence for the purpose of depriving other parties of use of the evidence. Generally, when a party intentionally fails to produce evidence that is within its reach, courts have applied a presumption that the evidence would have been detrimental to that party’s case. Randolph v. General Motors Corp., 93-1983 (La. App. 1 Cir. 11/10/94), 646 So. 2d 1019, 1026.

However, this presumption is not applicable when there is a reasonable explanation for failure to produce the evidence. Id. In Randolph v. General Motors Corp., General Motors had knowledge that it was at fault for an accident, so the court ruled that it should have led to the presumption that some sort of lawsuit would be brought against it for the accident. Additionally, General Motors was unable to provide a reasonable explanation for not producing the evidence. This begs an important question: if a party believes that it is not at fault for the accident, then is it reasonable to presume that there will be no lawsuit, and therefore, no need to preserve or produce evidence?

The Duty to Preserve Evidence

The duty to preserve evidence arises from the foreseeability of the need for the evidence in the future. Dennis v. Wiley, 2009-0236 (La. App. 1 Cir. 9/11/09), 22 So. 3d 189, 195. “Where a suit has not been filed and there is no evidence that a party knew a suit would be filed when the evidence was discarded[,] the theory of spoliation of evidence does not apply.” Quinn v. RISO Invs., Inc., 869 So. 2d 922, 927 (La. App. 4 Cir. 3/3/04) (citing Smith v. Jitney Jungle of Am., 802 So. 2d 988, 995 (La. App. 2 Cir. 12/5/01).

Louisiana courts have consistently held that the duty to preserve does not arise until the party has notice that evidence in its control is relevant to pending or imminent litigation. Rousell v. Circle K Store, Inc., 340 So. 3d 52, 56 (La. App. 1 Cir. 12/22/21). Although courts have not defined what exactly constitutes “notice,” some courts have ruled that “[t]he duty to preserve material evidence arises not only during litigation but also extends to that period before the litigation when a party reasonably should know that the evidence may be relevant to anticipated litigation.” Sayre v. PNK (Lake Charles), LLC, 188 So. 3d 428 (La. App. 3 Cir. 3/23/16).

Additionally, and importantly, the Louisiana Third Circuit has made it clear that a duty to preserve evidence is enforceable only if it arises from a statute, contract, special relationship between the parties, or an affirmative agreement or undertaking to preserve the evidence. Hypolite v. Scott Partners MLT, Inc., 19-704, pg. 9 (La. App. 3 Cir. 4/1/20), 297 So. 3d 868. It can also arise from a timely request or demand from the plaintiff.

The duty to preserve may also arise when a company has set procedures for preservation of ECM data following an accident. When a company has such procedures for preservation, that company should follow the rules that it has set out for itself. In Sayre v. PNK (Lake Charles), LLC, 15-859 (La. App. 3 Cir. 3/23/16), 188 So. 3d 428, the defendant company failed to follow its own detailed written policies and procedures for post-accident preservation. The Court applied the adverse presumption against litigants who had access to evidence and either did not make it available or destroyed it.  However, if the defendant does not have such written procedures, then the plaintiff is not entitled to an adverse presumption. Hypolite v. Scott Partners MTL, Inc., 19-704, p. 9 (La. App. 3 Cir. 4/1/20), 297 So. 3d 868, 874.

Fifth Circuit Ruling on Failure to Preserve

Although there are no Louisiana cases that are directly on point, there has been at least one Federal Fifth Circuit Court of Appeals case holding that the defendant did not fail to preserve ECM data. McCon v. Adolfo Perez & D&D Express Transp., 2018 U.S. Dist. LEXIS 207341 (S.D. Miss. 7/24/18). In McCon, the plaintiff claimed that, following a motor vehicle accident, the defendant’s failure to download the ECM data immediately after the accident constituted spoliation of evidence. The plaintiff argued that ECM data should be retrieved right after a crash because the accident data is overwritten and erased when subsequent events occur, such as hard braking. In fact, the accident data had been erased due to two hard brakes during a later trip. The Court held that there was no authority requiring the defendant to download and/or preserve the ECM data simply because it was involved in an accident.

Implications for Louisiana

There is no Louisiana law that requires a party to download ECM data after an accident. Additionally, the Louisiana Supreme Court has held that “no cause of action exists for negligent spoliation of evidence” and that “public policy in [Louisiana] precludes the existence of a duty to preserve evidence.” Reynolds v. Bordelon, 172 So. 3d 589 (La. 2015). However, the adverse presumption against a party who had access to evidence and did not make it available or destroyed it still exists. Id. at 600. Thus, it stands to reason that there can only be intentional destruction of evidence in Louisiana, with a party ignoring some statutory, contractual, noticed, or similar duty to preserve evidence.


Based on Louisiana jurisprudence, there is no duty to preserve ECM data following an accident simply because the accident occurred. Rather, the duty must arise from a statute, contract, relationship between the parties, affirmative agreement, written company procedure, or timely request from the plaintiff. If none of these circumstances are present, then there is no duty to preserve ECM data. Additionally, the Louisiana Supreme Court has only left room for intentional destruction of ECM evidence, as opposed to negligent spoliation of evidence.