Supreme Court of Texas 

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No. 20-0268 

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In re Kuraray America, Inc., 

Relator

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On Petition for Writ of Mandamus 

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PER CURIAM 

In this mandamus action arising out of a chemical release at a 

plant, the trial court ordered Relator Kuraray America, Inc., the 

defendant below, to produce cell-phone data from the employer-issued 

phones of five employees. Two of the five employees are supervisors—

for them, the trial court ordered production of cell-phone data for the 

six-week period before the chemical release. As to the remaining three 

employees—control-room board operators who reported to the two 

supervisors—the trial court ordered production of cell-phone data for the 

four-month period before the release. Relator challenges the trial court’s 

orders regarding production of all five employees’ cell-phone data on the 

ground the orders require production of information as to which 

relevance has not been established and thus are impermissibly 

overbroad. We agree and conditionally grant the writ. 
2 

Kuraray operates an ethylene vinyl-alcohol copolymer plant in 

Pasadena. In May 2018, a chemical reactor became over-pressurized 

and released ethylene vapor that caught on fire, resulting in multiple 

injuries and lawsuits. The lawsuits were transferred to a multidistrict 

litigation pretrial court for consolidated pretrial proceedings. See TEX.

GOV’T CODE § 74.162 (authorizing transfer of cases involving common 

questions of fact for consolidated pretrial proceedings). 

The ethylene release occurred during a plant turnaround—a 

scheduled stoppage of operations for maintenance and equipment 

replacement—that began in early April 2018 and lasted many weeks. 

About six weeks into the turnaround, between 12:53 a.m. and 7:00 a.m. 

on May 19, 2018, the temperature inside one of the plant’s reactors, the 

R-1201, dropped unexpectedly, causing the ethylene inside to condense 

from a gas to a liquid. When the reactor’s temperature rose again, its 

internal pressure rose rapidly. A high-pressure alarm went off at 8:51 

a.m. in the control room where two Kuraray board operators were 

monitoring the R-1201 and other reactors. Nine minutes later, around 

9:00 a.m., a second alarm, known as the “Hi Hi alarm,” activated and 

continued sounding every ten minutes. Within a few minutes after the 

first alarm sounded, the board operator monitoring the R-1201 opened 

a pressure control valve in an attempt to stabilize the reactor’s pressure 

and then opened it more after the Hi Hi alarm was first activated. The 

same board operator testified that he continued to respond to the 

alarms, but he did not realize the R-1201 was as close as it was to its 

maximum allowable pressure because he did not know that the R-1201’s 

maximum was lower than that of the other reactors. The pressure in 
3 

the R-1201 caused a rupture disk to burst at 10:28 a.m., releasing 

ethylene vapor that ignited and injured several nearby workers. 

The five employees whose cell-phone data is in dispute had 

different roles and levels of involvement in monitoring the R-1201 in the 

hours before the ethylene release: 

 Jeremy Neal was the board operator monitoring the R-1201 

from 5:30 p.m. on May 18 until his shift ended at 5:30 a.m. on 

May 19. Neal was thus on overnight duty when the R-1201’s 

internal temperature began dropping, but his shift ended 

hours before the alarms activated. 

 Troy Moorer was the board operator monitoring the R-1201 

from 5:30 a.m. until about 10:00 a.m., when he was tasked 

with monitoring another reactor. 

 Joe Jones, also a board operator, was initially monitoring 

other reactors that morning but was tasked with monitoring 

the R-1201 at around 10:00 a.m. when a supervisor instructed 

Jones to take over the R-1201 from Moorer. 

 Joe Zoller, a supervisor and former board operator, was “in 

and out” of the control room that morning but was 

continuously present and “watching” the board operators 

starting at around 10:00 a.m. 

 Mike Bowlin was the board operators’ direct supervisor but 

was not present in the control room on May 19. 

Plaintiffs asserted claims against Kuraray for negligence and 

gross negligence, but they did not allege that cell-phone use by any 

Kuraray employee constituted negligence or was a cause of the release. 

For its part, Kuraray collected the company-issued cell phones of several 

employees, including those working in the control room at the time of 

the release, and copied the cell-phone data. Plaintiffs sought production 

of “all information collected from all phones post incident,” with no time 

limitation. Kuraray initially offered to produce text messages and 
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photographs concerning the release from the phones of several 

employees who had some connection to the operations in the control 

room or may have been present in the control room that morning. 

Instead, two separate groups of plaintiffs moved to compel the 

production of all information collected from the cell phones. In their 

motions, Plaintiffs asserted that this information is relevant because a 

potential cause of the release was “cell phone usage and abuse by board 

operators.” Plaintiffs also asserted that evidence “pertaining to the 

activities of Kuraray’s employees during the startup of the line in 

question, the night before the incident, the day of the incident, and the 

incident itself, is highly relevant.” In support of their motions, Plaintiffs 

presented Zoller’s deposition testimony to the effect that, in the months 

before the release, Kuraray occasionally had a problem with employee 

cell-phone use in the control room. Plaintiffs also presented deposition 

testimony from Moorer that Kuraray had a policy prohibiting cell 

phones in the control room, although Moorer later clarified that 

Kuraray’s policy prohibited “abuse” of cell phones. In response, Kuraray 

argued, among other things, that the information sought was not 

relevant and therefore was not discoverable under Texas Rule of Civil 

Procedure 192.3. 

At a hearing, Plaintiffs argued that the cell-phone information 

was needed to determine whether employees in the control room might 

have been distracted by their phones when they should have been 

alerted to changing plant conditions that led to the release. In addition 

to the deposition testimony referenced in their motions, Plaintiffs 
5 

presented a January 23, 2018 email from an unknown sender1 to various 

Kuraray supervisors expressing concerns about “cell phone abuse” by 

board operators. During the hearing, Kuraray agreed to produce 

information regarding cell-phone activity by the board operators 

starting at 5:30 p.m. the night before the release. The trial court instead 

ordered Kuraray to produce cell-phone usage data for the board 

operators going back to January 23, the date of the anonymous email 

regarding “cell phone abuse.” The court further ordered Kuraray to 

produce cell-phone data for Zoller and Bowlin, the two supervisors, going 

back to April 6, the date on which Kuraray started the turnaround. 

Kuraray moved for reconsideration. It asserted that its analysis 

demonstrated that cell-phone use was not a contributing cause of the 

release. In particular, Kuraray contends the data show that none of the 

five employees was using a cell phone at a time when he should have 

been responding to the R-1201 alarms or other warning signs. According 

to Kuraray, the lack of any showing of a causal connection between 

cell-phone use and the release makes the cell-phone data irrelevant, 

rendering the trial court’s orders for production overbroad and beyond 

the permissible scope of discovery. 

Plaintiffs responded by reiterating that they were entitled to the 

cell-phone data because they had demonstrated that Kuraray had a 

history of issues with cell-phone abuse and distracted board operators. 

The trial court denied reconsideration. Further disputes regarding the 

1 The January 23 email was referenced during some of the depositions 

and at the hearing on Plaintiffs’ motion to compel, but it appears from the 

discussion that the email does not identify its sender. The email itself is not 

in the mandamus record. 
6 

scope of the order resulted in a third order detailing how the data should 

be produced for each of the five employees. Kuraray seeks mandamus 

relief from these orders.2

“A discovery order that compels production beyond the rules of 

procedure is an abuse of discretion for which mandamus is the proper 

remedy.” In re Nat’l Lloyds Ins. Co., 449 S.W.3d 486, 488 (Tex. 2014). 

Rule 192.3 limits discovery to matters that are “relevant to the subject 

matter of the pending action.” TEX. R. CIV. P. 192.3(a). While trial courts 

enjoy discretion in determining what is “relevant to the subject matter,” 

that discretion is not unlimited. See In re Nat’l Lloyds Ins. Co., 507 

S.W.3d 219, 223 (Tex. 2016) (“What is ‘relevant to the subject matter’ is 

to be broadly construed. These liberal bounds, however, have limits, and 

‘discovery requests must not be overbroad.’” (citation omitted) (quoting 

In re Nat’l Lloyds, 449 S.W.3d at 488)). A discovery request is 

impermissibly overbroad if it is not “reasonably tailored to include only 

matters relevant to the case.” Id. at 223-24 (quoting Texaco, Inc. v. 

Sanderson, 898 S.W.2d 813, 815 (Tex. 1995)). It is the burden of the 

party seeking discovery to demonstrate that the requested documents 

are relevant and therefore discoverable under Rule 192.3. In re TIG Ins. 

Co., 172 S.W.3d 160, 167 (Tex. App.—Beaumont 2005, orig. proceeding); 

see In re Dana Corp., 138 S.W.3d 298, 302 (Tex. 2004) (concluding that 

2 The challenged orders were issued by Judge Daryl Moore of the 333rd 

District Court, who was appointed as the pretrial judge by the multidistrict 

litigation panel. After Kuraray filed its mandamus petition, Judge Moore left 

the bench, and the MDL panel assigned Judge Lauren Reeder of the 234th 

District Court as the pretrial judge. We abated the case to allow Judge Reeder 

to reconsider the challenged orders, see TEX. R. APP. P. 7.2(b), but she declined. 
7 

a discovery request seeking insurance policies that predated plaintiffs’ 

exposure to asbestos was overly broad because plaintiffs failed to 

establish the potential applicability of those policies to the lawsuit). 

Where a discovery order compels production of “patently irrelevant or 

duplicative documents,” there is no adequate remedy by appeal because 

the order “imposes a burden on the producing party far out of proportion 

to any benefit that may obtain to the requesting party.” In re CSX Corp., 

124 S.W.3d 149, 153 (Tex. 2003) (quoting Walker v. Packer, 827 S.W.2d 

833, 843 (Tex. 1992)). 

Quite unsurprisingly, discovery requests for cell-phone data have 

become commonplace in recent years. While our Court has not yet had 

occasion to apply the legal principles governing discovery in this context, 

our courts of appeals have grappled with the issue. From these cases, 

we glean some key principles that should guide trial courts’ careful 

management of cell-phone-data discovery. First, to be entitled to 

production of cell-phone data, the party seeking it must allege or provide 

some evidence of cell-phone use by the person whose data is sought at a 

time when it could have been a contributing cause of the incident on 

which the claim is based. If the party seeking the discovery satisfies 

this initial burden, the trial court may order production of cell-phone 

data, provided its temporal scope is tailored to encompass only the 

period in which cell-phone use could have contributed to the incident.3 

In other words, a trial court may not, at this stage, order production of 

3 A trial court ordering production of cell-phone data should of course 

also consider any objections by the producing party concerning the type or 

subject-matter of the data requested, as well as any valid privacy, 

confidentiality, or proportionality objections. 
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a person’s cell-phone data for a time at which his use of a cell phone 

could not have been a contributing cause of the incident. Only if this 

initial production indicates that cell-phone use could have contributed 

to the incident may a trial court consider whether additional discovery 

regarding cell-phone use beyond that timeframe may be relevant. 

Our courts of appeals have correctly granted mandamus relief 

where trial courts ordered production of cell-phone data (1) without a 

basis for concluding that cell-phone use may have contributed to the 

incident on which the claim is based or (2) for a time period broader than 

the time during which cell-phone use could reasonably be found to have 

been a contributing cause of the incident. For example, in In re Padilla, 

the Austin Court of Appeals granted mandamus relief when a trial court 

ordered production of a driver’s cell-phone records for fourteen days 

before and fourteen days after a car accident. No. 03-18-00477-CV, 2018 

WL 4087733, at *2 (Tex. App.—Austin Aug. 28, 2018, orig. proceeding). 

The plaintiff initially sought the defendant driver’s cell-phone records 

for the period encompassing thirty days before and thirty days after the 

accident. Id. at *1. The defendants, for their part, agreed to produce 

the driver’s cell-phone records for the period one hour before and one 

hour after the accident. Id. The trial court split the proverbial baby, 

ordering production of cell-phone records for the period fourteen days 

before the accident and fourteen days after. Id. Much like in this case, 

the plaintiff in Padilla argued the temporal scope of discovery should 

not be limited to a narrow window immediately surrounding the 

accident because she sought to show not only that the driver’s cell-phone 

use might have caused the accident but also that the driver’s employer 
9 

negligently failed to train its drivers or to create and enforce a policy 

prohibiting cell-phone use while driving. Id. at *2. The court of appeals 

disagreed, explaining that the plaintiff did not plead that cell-phone use 

caused the accident, the plaintiff’s claimed right to cell-phone records 

“presuppose[s] and depend[s] on the use of the cell-phone by [the driver] 

at or near the time of the incident,” and the plaintiff’s request “seeks 

information well beyond that timeline and scope.” Id. Accordingly, it 

directed the trial court to vacate its order requiring production of the 

phone records. Id.

More recently, the Tyler Court of Appeals granted mandamus 

relief when a trial court ordered production of a truck driver’s cell phone 

for inspection and examination. In re UV Logistics, LLC, No. 12-20-

00196-CV, 2021 WL 306205, at *1 (Tex. App.—Tyler Jan. 29, 2021, orig. 

proceeding). The plaintiff alleged that the defendant was distracted by 

his cell phone and presented a witness affidavit attesting the truck 

driver said he was looking at his phone at the time of the accident. Id.

at *1, *4. The plaintiff argued she was entitled to inspect the cell phone 

to prove both whether the truck driver was using it at the time of the 

accident and whether he regularly used it while driving. Id. at *4. While 

the court of appeals acknowledged that the plaintiff demonstrated a 

“reasonable need” for this information, id., it granted mandamus relief 

and vacated the order, concluding the trial court abused its discretion 

by ordering production without limitation. Id. at *5. 

Applying these same principles here, we conclude that the trial 

court abused its discretion by ordering production of Kuraray’s 

employees’ cell-phone data for a six-week or four-month period without 
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a showing that each employee’s use of his cell phone on May 18 or 19 

could have been a contributing cause of the ethylene release. Plaintiffs’ 

petitions do not allege that cell-phone use by anyone was a contributing 

cause of the release. Instead, they assert in their motions to compel the 

general proposition that the release may have been caused by “cell 

phone usage and abuse by board operators.” Relying on this assertion, 

the trial court ordered Kuraray to produce four months of cell-phone 

data for the three board operators and six weeks for the supervisors. 

This was impermissibly overbroad. 

The question that discovery of cell-phone data is meant to answer 

in this case is whether any Kuraray employee was distracted by his cell 

phone at a time when he should have been taking action to prevent the 

release, such that his use of the cell phone reasonably could be found to 

be a contributing cause of the release. Plaintiffs do not dispute that the 

events to which they allege the employees should have been responding 

began, at the earliest, during the May 18 night shift, which started at 

5:30 p.m. And Kuraray does not dispute that Plaintiffs are entitled to 

discover the board operators’ cell-phone data during on-duty hours from 

the start of that shift until the release occurred—approximately 

seventeen hours later. But the trial court instead ordered Kuraray to 

produce cell-phone data for far broader time periods: either four months 

preceding the release (in the case of the three board operators) or six 

weeks preceding the release (in the case of the two supervisors). 

Plaintiffs argue that cell-phone data from days, weeks, and 

months before the release is relevant because Kuraray negligently failed 

to supervise its employees and failed to implement adequate policies and 
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procedures to protect against cell-phone misuse. But Kuraray’s policies 

regarding cell-phone use and its alleged failure to supervise its 

employees are relevant only if there is some evidence that cell-phone use 

could have been a contributing cause of the release itself. In the absence 

of such a showing, the employees’ earlier cell-phone usage, like 

Kuraray’s cell-phone policies and success or failure in enforcing them, is 

neither relevant nor discoverable. 

The record shows the extent of each of the five employees’ 

cell-phone use during the seventeen hours in which cell-phone 

distraction at work could potentially have made a difference in how 

events unfolded on May 19. The trial court should not have ordered 

production of cell-phone data outside this time period for any of the 

employees without first undertaking a person-by-person analysis of 

whether cell-phone use within that time period could have been a 

contributing cause of the release. 

In fact, the mandamus record shows that three of the five 

employees had no cell-phone use during this seventeen-hour period at 

any time when it might have distracted them from taking action to 

prevent the release: 

 Joe Jones: no evidence of any cell-phone activity after he began 

monitoring the R-1201 at 10:00 a.m.4

 Joe Zoller: no evidence of any cell-phone activity for the thirty 

minutes before the release, during which he testified he was 

4 The mandamus record shows Jones received seven texts before 10:00 

a.m. and made a three-word response to one of them. But all of this occurred 

before he was tasked with monitoring the R-1201. 
12 

in the control room and watching what the board operators 

were doing. 

 Mike Bowlin: no evidence he was in the control room before 

the release and no evidence showing how his two seconds of 

cell-phone activity approximately 90 minutes before the 

release from a location outside the control room could have 

contributed to the release. 

Plaintiffs do not dispute this evidence. Instead, they argue that it, 

combined with Kuraray’s alleged problems with cell-phone abuse, is 

sufficient to raise a fact issue as to whether these employees were 

distracted by their phones, making their earlier cell-phone data 

relevant. We disagree. There was no showing of any cell-phone activity 

by these three employees that reasonably could be found to be a 

contributing cause of the release. Accordingly, the trial court abused its 

discretion in ordering the production of their earlier cell-phone data. 

That leaves Neal and Moorer, the two board operators whose 

records do reflect some cell-phone activity while they were in the control 

room monitoring the R-1201 in the hours preceding the release: 

 Jeremy Neal, the board operator on duty from 5:30 p.m. on 

May 18 until 5:30 a.m. on May 19: records show ten seconds of 

cell-phone activity at about 1:19 a.m., when the R-1201’s 

temperature was dropping. 

 Troy Moorer, the board operator monitoring the R-1201 

beginning at 5:30 a.m. on May 19: received two texts and 

responded to one approximately one hour before the release. 

While these two employees’ records reflect some cell-phone use during 

the timeframe in which the R-1201’s temperature was dropping (in 

Neal’s case) and after alarms were activated (in Moorer’s), as the party 

seeking discovery, Plaintiffs bore the burden to show, and the trial court 

had an obligation to consider, whether the use—its nature, duration, 
13 

and frequency in the given context—could support a finding that 

cell-phone use contributed to the release. See In re TIG, 172 S.W.3d at 

168 (“The burden to propound discovery complying with the rules of 

discovery should be on the party propounding the discovery, and not on 

the courts to redraft overly broad discovery . . . .”); cf. Lozano v. Lozano, 

52 S.W.3d 141, 148 (Tex. 2001) (“[I]n cases with only slight 

circumstantial evidence, something else must be found in the record to 

corroborate the probability of the fact’s existence or non-existence.”). In 

the absence of such a showing, it was an abuse of discretion to order 

production of the employees’ earlier cell-phone data.5

Finally, we conclude Kuraray lacks an adequate remedy by 

appeal because its compliance with the discovery orders would require 

the production of information that has not been shown to be relevant. 

See In re Nat’l Lloyds Ins. Co., 532 S.W.3d 794, 803 (Tex. 2017) 

(“Mandamus relief is appropriate when . . . a trial court compels 

production of irrelevant information . . . .”); In re CSX, 124 S.W.3d at 

153 (concluding there is no adequate remedy by appeal from a discovery 

order requiring production of patently irrelevant documents). 

Without hearing oral argument, see TEX. R. APP. P. 52.8(c), we 

conditionally grant Kuraray’s petition for writ of mandamus and direct 

5 We do not foreclose the possibility that Plaintiffs ultimately may show 

themselves entitled to discovery of Neal’s or Moorer’s cell-phone data outside 

the seventeen hours preceding the release. If Neal’s or Moorer’s brief 

cell-phone use during this period, considered in context of the surrounding 

circumstances, is shown to be a potential contributing cause of the release, 

then evidence of cell-phone use outside this time period may become relevant. 

But no such showing was made here; accordingly, it is sufficient for today to 

conclude that the trial court abused its discretion by adopting a four-month 

temporal scope in the first instance. 
14 

the trial court to vacate its orders requiring Kuraray to produce 

cell-phone data for Neal, Moorer, Jones, Zoller, and Bowlin. We are 

confident the trial court will comply, and the writ will issue only if it 

does not. 

OPINION DELIVERED: December 9, 2022