         IN THE UNITED STATES COURT OF APPEALS
                  FOR THE FIFTH CIRCUIT United States Court of Appeals
                                                 Fifth Circuit

                                                          FILED
                                                         March 2, 2012

                                                         Lyle W. Cayce
                              No. 10-30249                    Clerk


IN RE: KATRINA CANAL BREACHES LITIGATION.

********************

NORMAN ROBINSON; KENT LATTIMORE; LATTIMORE & ASSOCIATES;
TANYA SMITH,

                                 Plaintiffs-Appellees-
                                 Cross-Appellants,
versus

UNITED STATES OF AMERICA,

                                 Defendant-Appellant-
                                 Cross-Appellee.

********************

MONICA ROBINSON,

                                 Plaintiff-Appellee-
                                 Cross-Appellant,

versus

UNITED STATES OF AMERICA,

                                 Defendant-Appellant-
                                 Cross-Appellee.

********************
                                         Consolidated with
                                           No. 10-31054


IN RE: KATRINA CANAL BREACHES LITIGATION.

********************



                                         Consolidated with
                                           No. 11-30808


IN RE: KATRINA CANAL BREACHES LITIGATION.

----------------------------------------------

UNITED STATES OF AMERICA,
on Behalf of United States Army Corps of Engineers,

                                                     Petitioner.




                      Appeals from the United States District Court
                          for the Eastern District of Louisiana




Before SMITH, PRADO, and ELROD, Circuit Judges.
JERRY E. SMITH, Circuit Judge:


        Decades ago, the Army Corps of Engineers (the “Corps”) dredged the Mis-
sissippi River Gulf Outlet (“MRGO”), a shipping channel between New Orleans
and the Gulf of Mexico, as well as levees alongside the channel and around the
city. The Corps’s negligence in maintaining the channel, grounded on a failure

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                          Nos. 10-30249, 10-31054, 11-30808

to appreciate certain hydrological risks, caused levees to fail and aggravated the
effects of 2005’s Hurricane Katrina on the city and its environs.
       Claimants filed hundreds of lawsuits, many of which were consolidated
before the district judge a quo. That court worked with plaintiffs’ litigation com-
mittees to identify several categories of plaintiffs and individual “bellwether”
plaintiffs. This opinion concerns three groups of bellwether plaintiffs, all suing
the United States for flood damages. One group went to trial; three of its plain-
tiffs prevailed on all claims, and four did not. Another group was dismissed
before trial when the government was found immune. The third has survived
motions to dismiss and is proceeding to trial. All losing parties have appealed;
the government has also petitioned for a writ of mandamus to stay the third
group’s trial pending issuance of this opinion. We AFFIRM each of the judg-
ments and DENY the petition.


                                     I. Background.1
       In 1943, Congress requested a report from the Chief of Engineers, Secre-
tary of the Army, investigating ways to make the Port of New Orleans more
accessible for maritime and military use. That request led to the authorization
of MRGO in 1956. The channel was built to its full dimensions by 1968 and
afforded a shorter shipping route between the Gulf of Mexico and New Orleans.
As the district court noted, the channel, as originally designed, “was to be 36 feet
deep and 500 feet wide, increasing at the Gulf of Mexico to 38 feet deep and 600
feet wide.” In re Katrina Canal Breaches Consol. Litig., 647 F. Supp. 2d 644, 717
(E.D. La. 2009). MRGO was cut through virgin coastal wetlands at a depth that
exposed strata of so-called “fat clay,” a form of soil soft enough that it will move


       1
        The district court’s factfinding spans dozens of pages. Because parties have challenged
almost none of those factual findings, we will summarize only those few facts needed to explain
the applications of law included here.

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                            Nos. 10-30249, 10-31054, 11-30808

if made to bear a load. The channel’s original designers considered and rejected
armoring its banks with foreshore protection, leaving them vulnerable to
erosion.
       During the design and construction of MRGO, the Corps also implemented
the Lake Pontchartrain and Vicinity Hurricane Protection Plan (“LPV”). Pur-
suant to that plan, the Corps constructed, inter alia, the New Orleans East Unit,
levees protecting New Orleans East; the Chalmette Area Unit, levees protecting
the Ninth Ward and St. Bernard Parish; and higher floodwalls in the outfall
canals at 17th Street, Orleans Avenue, and London Avenue.
       Over the years, MRGO’s lack of armoring or foreshore protection resulted
in substantial erosion of its banks, largely from wave wash from wakes left by
channel-going vessels. MRGO eventually reached a total average width of 1970
feet, well over three times its authorized width.
       Though the Corps eventually added foreshore protection in the 1980s, that
delay allowed the channel to widen considerably, destroying the banks that
would have helped to protect the nearby Reach 2 levee (in the Chalmette Area
Unit) from front-side wave attack as well as loss of height. The increased chan-
nel width added more fetch2 as well, allowing for a more forceful frontal wave
attack on the levee.
       MRGO’s expansion thus allowed Hurricane Katrina to generate a peak
storm surge capable of breaching the Reach 2 Levee and flooding the St. Bernard
polder.3 Separately from MRGO, the hurricane also caused the 17th Street,
Orleans Avenue, and London Avenue levees to breach.
       Over 400 plaintiffs sued in federal court to recover for Katrina-related


       2
         Fetch is defined as the width of open water that wind can act upon. The height of
waves (such as the storm surge created by Katrina) is a function of the depth of the water as
well as the width of the expanse (i.e., the fetch) over which wind impacts the water.
       3
           A polder is a tract of low land reclaimed from a body of water.

                                                4
                          Nos. 10-30249, 10-31054, 11-30808

damages, many naming the federal government as a defendant. Seven plaintiffs
(the “Robinson plaintiffs”) from that number went to trial. The court issued its
impressive rulings in thorough opinions.4 The court found that neither the Flood
Control Act of 1928 (“FCA”), 33 U.S.C. § 702, nor the discretionary-function
exception (“DFE”) to the Federal Tort Claims Act (“FTCA”), 28 U.S.C. § 2680(a),
protected the government from suit; after nineteen days of trial, the court found
that three plaintiffs had proven the government’s full liability and four had not.
Another group of plaintiffs (the “Anderson plaintiffs”) had their cases dismissed
on the government’s motion, the court finding both immunities applicable. Still
a different group (the “Armstrong plaintiffs”) are preparing for trial of their own
case against the government.
       The government appeals its losses in Robinson; the losing Robinson plain-
tiffs cross-appeal. The Anderson plaintiffs have appealed as well. On the theory
that a favorable ruling here might moot the pending Armstrong trial, the govern-
ment petitions this court for a writ of mandamus to order the district court to
stay trial until we issue an opinion in Robinson and Anderson. The three cases
have been consolidated on appeal.


                                II. Standard of Review.
       A district court’s construction of immunity under the FCA and of the
FTCA’s DFE is subject to de novo review. See Withhart v. Otto Candies, L.L.C.,
431 F.3d 840, 841 (5th Cir. 2005). Factual findings are reviewed for clear error.
Lehmann v. GE Global Ins. Holding Corp., 524 F.3d 621, 624 (5th Cir. 2008).



       4
        See In re Katrina Canal Breaches Consol. Litig., No. 2:05-CV-4182, 2011 U.S. Dist.
LEXIS 16351 (E.D. La. Feb. 11, 2011); In re Katrina Canal Breaches Consol. Litig., 647 F.
Supp. 2d 644, 699 (E.D. La. 2009); In re Katrina Canal Breaches Consol. Litig., 577 F. Supp.
2d 802 (E.D. La. 2008); In re Katrina Canal Breaches Consol. Litig., 533 F. Supp. 2d 615 (E.D.
La. 2008).

                                              5
                        Nos. 10-30249, 10-31054, 11-30808

                  III. The FCA: Construction and Application.
      Under the Central Green-Graci test, the government enjoys immunity only
from damages caused by floodwaters released on account of flood-control activity
or negligence therein. Some Katrina-related flooding was caused not by flood-
control activity (or negligence therein) but by MRGO, a navigational channel
whose design, construction, and maintenance cannot be characterized as flood-
control activity. Therefore, the FCA does not immunize the government against
liability for that flooding.


                         A. The Scope of FCA Immunity.
      The FCA “was the Nation’s response to the disastrous flood in the Missis-
sippi River Valley in 1927.” United States v. James, 478 U.S. 597, 606 (1986).
The law enacted “a comprehensive ten-year program for the entire [Mississippi
River] valley, embodying a general bank protection scheme, channel stabilization
and river regulation, all involving vast expenditures of public funds.” United
States v. Sponenbarger, 308 U.S. 256, 262 (1939). Staggering in scope, the FCA’s
flood-control program was “the largest public works project undertaken up to
that time in the United States.” James, 478 U.S. at 606.
      The FCA predated the FTCA and the latter’s abrogation of sovereign
immunity from tort liability, but Congress nonetheless included Section 702c in
the FCA, 33 U.S.C. § 702c, which affirms the government’s sovereign immunity
in the flood-control context: “No liability of any kind shall attach to or rest upon
the United States for any damage from or by floods or flood waters at any place.”
The Supreme Court has read Section 702c’s legislative history as reflecting Con-
gress’s “consistent concern for limiting the Federal Government’s financial lia-
bility to expenditures directly necessary for the construction and operation of the
various projects” funded by the FCA. James, 478 U.S. at 607. This court had
similarly emphasized Congress’s reluctance to build flood-control projects with-

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                       Nos. 10-30249, 10-31054, 11-30808

out a guarantee of immunity: “[T]he immunity from liability for floodwater dam-
age arising in connection with flood control works was the condition upon which
the government decided to enter into the area of nationwide flood control pro-
grams.” Graci v. United States, 456 F.2d 20, 26 (5th Cir. 1971) (internal quota-
tion marks omitted).
      Although the text of Section 702c could not more broadly preserve immun-
ity, in Graci we read the FCA and its legislative history to include a limitation.
We determined that it was unreasonable “to suppose that in exchange for its
entry into flood control projects[,] the United States demanded complete immun-
ity from liability for the negligent and wrongful acts of its employees uncon-
nected with flood control projects.” Id. We therefore held that the Graci plain-
tiffs’ claims were not barred by the FCA because they alleged flood water dam-
age caused by “the negligence of the United States unconnected with any flood
control project.” Id. at 27.
      The government proposes a broader interpretation of FCA immunity that
would hold the government immune where plaintiffs allege damage caused by
flood waters that a federal flood-control project had failed to contain. If the flood
waters at issue are connected to a flood-control project, the government argues,
the claim is barred. Language in James supports the government’s position: The
Court read Section 702c’s “plain language” and defined the phrase “floods or
flood waters” to mean “all waters contained in or carried through a federal flood
control project for purposes of or related to flood control, as well as to waters that
such projects cannot control.” James, 478 U.S. at 605. The issue in James, how-
ever, was whether Section 702c’s reference to “‘damage’ encompassed not just
property damage, but also personal injuries and death.” Cent. Green Co. v.
United States, 531 U.S. 425 (2001).
      In Central Green, the Court most recently considered the scope of Section
702c immunity and the meaning of the phrase “floods and flood waters.” The

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                        Nos. 10-30249, 10-31054, 11-30808

Ninth Circuit—purporting to follow James’s definition of “floods and flood
waters”—had focused on whether the source of water that caused the com-
plained-of damage was part of a federal flood-control project; that court ulti-
mately concluded that immunity attached “‘solely because [the Madera Canal]
is a branch of the Central Valley Project.’” Id. at 428 (quoting Cent. Green Co.
v. United States, 177 F.3d 834, 839 (9th Cir. 1999)). In so holding, the Ninth Cir-
cuit “recognized that the Government would probably not have enjoyed immun-
ity in at least three other Circuits where the courts require a nexus between
flood control activities and the harm done to the plaintiff.” Id. The Court
granted certiorari to resolve that circuit split and framed the issue as “whether
[‘floods or flood waters’] encompass all the water that flows through a federal
facility that was designed and is operated, at least in part, for flood control pur-
poses.” Id. at 427.
      With the meaning of the phrase “floods and flood waters” squarely before
it, the Court rejected James’s definition as “confusing dicta . . . that, if read liter-
ally, . . . sweeps so broadly as to make little sense,” id. at 431; the Central Green
Court set about narrowing the scope of Section 702c immunity by shifting the
analytical focus away from the water’s presence in a federal flood-control project.
Under the Ninth Circuit’s interpretation of James, waters constituted “floods or
flood waters,” and immunity applied where the government was linked to the
waters through the mere presence of a federal flood-control project. In Central
Green, the Court noted that “the text of the statute does not include the words
‘flood control project,’” id. at 434, so the scope of Section 702c is not determined
“by the character of the federal project or the purposes it serves, but by the char-
acter of the waters that cause the relevant damage and the purposes behind
their release,” id. Waters that constitute “floods or flood waters” within the
meaning of Section 702c, therefore, are not all waters that pass through a fed-
eral flood-control project, but are instead waters of a certain “character.”

                                           8
                       Nos. 10-30249, 10-31054, 11-30808

      Under Central Green, determining whether the water that caused damage
had this immune “character” has become the heart of the Section 702c inquiry.
The Court exemplified how water attains this “character” by contrasting James
with Henderson v. United States, 965 F.2d 1488 (8th Cir. 1992).
      In James, 478 U.S. at 612, the Court determined that the government was
immune from suit. There, the plaintiffs were injured when the Corps opened
gates in flood-control projects to release water from reservoirs that had reached
flood stage. Id. at 600-01. Notably, the gates were opened as part of the projects’
flood-control function. Id. The Central Green Court distinguished James from
Henderson, in which the plaintiff was injured when the Corps opened gates in
a flood-control project to produce hydroelectric power. See Henderson, 965 F.2d
at 1490. The water in James was “flood waters,” stated the Court, but the water
in Henderson was not. Cent. Green, 531 at 436.
      The only factual difference between James and Henderson is that in
James, the Corps acted to control a flood, whereas in Henderson, its activity was
entirely unrelated to flood control. Thus, after Central Green, waters have the
immune character of “flood waters” if the government’s link to the waters is
through flood-control activity. That is to say, the government’s acting upon
waters for the purpose of flood control is flood-control activity, and flood-control
activity is what gives waters an immune “character.” We therefore reject the
government’s interpretation of the scope of Section 702c and conclude, instead,
that the United States enjoys immunity under Section 702c of the FCA only
where damages result from waters released by flood-control activity or negli-
gence therein.


         B. The MRGO-St. Bernard Polder Plaintiffs: No Immunity.
      Plaintiffs Anthony Franz, Jr., Lucille Franz, Kent Lattimore, Lattimore
and Associates, and Tanya Smith allege that the operation and maintenance of

                                         9
                      Nos. 10-30249, 10-31054, 11-30808

MRGO caused the levee along Reach 2 of MRGO to be breached, resulting in the
flooding of the St. Bernard polder. The district court found that a combination
of erosion caused by MRGO (which could have been prevented through foreshore
protection) and destruction of wetland vegetation caused by increased salinity
levels on account of MRGO’s operation led to the breaches in the Reach 2 levee.
The court concluded that MRGO was a navigational, not flood-control, project
and, unlike the canals in Anderson, wholly extrinsic to the LPV.
      The court analogized MRGO to a Navy vessel that, as a result of negligent
operation, crashes through a levee causing a flood: Though the levee would be
a flood-control project, the cause of the waters’ releaseSSnegligent operation of
a Navy vesselSSwould not be the flood-control project or its negligent operation,
but rather the negligence in a wholly extrinsic government action. Thus, the
government would be afforded no immunity under Section 702c. Similarly, the
court ruled, the negligently maintained MRGO acted upon the levees in a way
that caused them to be breached during Hurricane Katrina, and, because MRGO
was not a flood-control project and was separate from the LPV, no immunity
should attach under Section 702c.
      But the government maintains that, instead of being distinct from one
another, MRGO and the LPV were intertwined. Because the failure to imple-
ment foreshore protection (as opposed to continued dredging of MRGO) caused
the levee breach, the government argues that foreshore protection would have
been done solely to benefit the levee system, a flood-control project. Thus, the
government argues, the Corps’s actions with respect to MRGO were relevant
precisely because of their asserted impact on the Reach 2 levees; the government
boils the plaintiffs’ claim down to “the government did not take adequate mea-
sures to ensure that the Reach 2 levee would be able to restrain flood waters.”
Consequently, the government says that the claim should be barred by Sec-
tion 702c.


                                       10
                       Nos. 10-30249, 10-31054, 11-30808

      Under the district court’s rule for applying Section 702cSS“immunity
arises where damage is caused by flood waters emanating from a flood control
project,” In re Katrina Canal Breaches, 577 F. Supp. 2d at 824SSthe negligent
maintenance of MRGO arguably does not create Section 702c immunity. As the
court held, the lack of foreshore protection was properly allocable to MRGO (a
navigational project), not the LPV (a flood-control project). Costs of the foreshore
protection were to be charged to MRGO project and were initially envisioned to
protect the channel width and maintain navigability. “Thus,” the district court
concluded, “the failures at issue here are extrinsic to the LPV and are not subject
to § 702c immunity.” In re Katrina Canal Breaches, 647 F. Supp. 2d at 699.
      Our interpretation of Section 702c and the caselaw, however, provides a
rule slightly different from the district court’s. Instead of its strictly categorical
approach, which would have immunity attach only where a flood was caused by
a project that had the purpose of flood control, we recognize immunity for any
flood-control activity engaged in by the government, even in the context of a pro-
ject that was not primarily or substantially related to flood control. Thus, for
example, if the government had attempted foreshore protection inside MRGO,
but that protection (whether by design or negligence) caused or exacerbated flood
damage, the district court’s rule would grant the Corps no immunity, because
the MRGO was not a flood-control project. Our rule, by contrast, attaches
immunity if the foreshore protection had flood control as its purpose—that is, if
installing and maintaining foreshore protection was a flood-control activity
regardless of the nature of MRGO, the overall project.
      To assess the St. Bernard plaintiffs’ argument, then, we must determine
whether the Corps’s decision to dredge MRGO instead of implementing foreshore
protection constitutes flood-control activity qualifying for Section 702c immunity.
The government would contend that, because foreshore protection would have
been done instead of dredging for the sole purpose of protecting the levees, the

                                         11
                         Nos. 10-30249, 10-31054, 11-30808

decision to dredge was flood-control activity protected by Section 702c. Even
under our formulation instead of the district court’s, the government’s defense
fails.
         The district court found that “the Corps clearly took the position that its
primary mission was to keep the shipping channel open to deep draft traffic
regardless of the consequences.” Id. at 660. Accordingly, the Corps chose to
dredge MRGO to keep it navigable rather than implement costlier foreshore pro-
tection, which would have had the dual purpose of keeping MRGO navigable and
protecting the levees. Thus, even in the context of MRGO, the Corps took no
action that could be characterized as flood-control activity. The only conceivable
flood-control activity is the failure of the government to implement foreshore pro-
tection, the very omission complained of by the plaintiffs. Such an omission can-
not provide the basis for immunity under Section 702c, lest all flood damage
caused by government activity be regarded as a result of (a lack of) flood-control
activity.
         The district court’s naval analogy is apt. There, a negligent government
activity (operating a ship) wholly unrelated to flood control causes a flood,
destroying another government project (a levee). Though one could imagine a
plaintiff’s saying that the Navy was negligent in not creating an onboard warn-
ing system preventing its ship from running into the levee, that hypothetical
system does not transform the operation of the Navy vessel into a flood-control
activity. To use another analogy, suppose the government builds an Army base
on the banks of the Mississippi River. Because of soft soil, the weight of its
structures depresses the land and causes flooding to nearby farms during a
heavy rain. Although the government might argue that the Army could have
built dikes to prevent the flooding, that hypothetical solution does not transform
the building of a base into a flood-control activity, or the failure to build dikes
into negligence in flood-control activity. In each example, the government is neg-


                                          12
                       Nos. 10-30249, 10-31054, 11-30808

ligent, but in nautical or construction activity, not flood control.
      Thus, the government cannot claim Section 702c immunity for MRGO’s
role in breaching the Reach 2 levee. The dredging of MRGO was not a flood-
control activity, nor was MRGO so interconnected with the LPV as to make it
part of the LPV. Therefore, the flood waters that destroyed the plaintiffs’ prop-
erty were not released by any flood-control activity or negligence therein.


      C. The MRGO-New Orleans East Plaintiffs: Immunity Irrelevant.
      The district court decided that plaintiffs Norman and Monica Robinson
were not entitled to relief for reasons unrelated to the FCA. Specifically, the
court reasoned that the Corps had no duty to build a surge-protection barrier
and that any negligence in operating or maintaining MRGO did not cause the
Robinsons’ injuries, which would have occurred had MRGO remained at its
design width. Id. at 660. Because we uphold the district court’s factual findings
infra, there is no need to analyze Section 702c immunity as to the Robinsons.


                D. The Anderson Plaintiffs: Immunity Applies.
      The Anderson plaintiffs allege that they were harmed by the breaching of
the levees along the 17th Street, London Avenue, and Orleans Avenue Canals
caused by the negligent dredging of the 17th St. Canal and the levees’ negligent
design and construction. The district court, in considering the government’s
motion to dismiss, took judicial notice of the fact that those levees were con-
structed as part of the LPV, and the canals themselves were incorporated by
Congress into the overall LPV project. Id. at 637-38. Although the design and
plan for those levees and canals may not have been prudent, they were ulti-
mately approved by Congress. And though the dredging of the 17th St. Canal
may have been negligent, the canal was part of the LPV. Because those canals
were designed to prevent flooding either by creating drainage or by preventing

                                        13
                       Nos. 10-30249, 10-31054, 11-30808

storm surge with levees, and were fully incorporated in the LPV plan, their
design and dredging are flood-control activities. Thus, because the waters that
damaged the Anderson plaintiffs’ property were allegedly released by negligence
in flood-control activity, the Corps is immune under Section 702c.


                 IV. Construction and Application of the DFE.
      The DFE to the FTCA does not immunize the government against dam-
ages resulting from flooding caused by Katrina’s effects on MRGO. Under the
Berkovitz-Gaubert test, the government enjoys immunity only where its discre-
tionary judgments are susceptible to public-policy analysis. The key judgment
made by the Corps, however, involved only the (mis-)application of objective sci-
entific principles and not any public-policy considerations: The Corps misjudged
the hydrological risk posed by the erosion of MRGO’s banks. Therefore, the gov-
ernment should not enjoy DFE immunity against the resultant flooding.
      The DFE bars suit on any claim that is “based upon the exercise or perfor-
mance or the failure to exercise or perform a discretionary function or duty on
the part of a federal agency or an employee of the Government, whether or not
the discretion involved be abused.” 28 U.S.C. § 2680(a). The purpose of the DFE
“is to prevent judicial second-guessing of legislative and administrative decisions
grounded in social, economic, and political policy through the medium of an
action in tort.” Spotts v. United States, 613 F.3d 559, 568 (5th Cir. 2010) (inter-
nal quotation marks omitted).
      “The Supreme Court has developed a two-part test for determining
whether the federal government’s conduct qualifies as a discretionary function
or duty.” Freeman v. United States, 556 F.3d 326, 336-37 (5th Cir. 2009). First,
the conduct must involve “an element of judgment or choice.” Id. at 337 (quoting
United States v. Gaubert, 499 U.S. 315, 322 (1991)) (other citation omitted). “If
a statute, regulation, or policy leaves it to a federal agency or employee to deter-

                                        14
                         Nos. 10-30249, 10-31054, 11-30808

mine when and how to take action, the agency is not bound to act in a particular
manner and the exercise of its authority is discretionary.” Id. (citation omitted).
“On the other hand, [t]he requirement of judgment or choice is not satisfied and
the discretionary function exception does not apply if a federal statute, regula-
tion, or policy specifically prescribes a course of action for an employee to follow,
because the employee has no rightful option but to adhere to the directive.”“
Id. (internal quotation marks omitted).
      Second, the DFE “protects only governmental actions and decisions based
on considerations of public policy.” Id. (citations omitted). The “proper inquiry”
is not whether the decisionmaker “in fact engaged in a policy analysis when
reaching his decision but instead whether his decision was susceptible to policy
analysis.” Spotts, 613 F.3d at 572 (emphasis removed) (internal quotation marks
omitted). Under Gaubert, 499 U.S. at 324, “the very existence” of a law or regu-
lation allowing a government employee discretion (satisfying Berkovitz’s first
prong) “creates a strong presumption that a discretionary act authorized by the
regulation involves consideration of the same policies which led to the promulga-
tion of the regulations.”


        A. Applying the DFE to the Corps’s Failure to Contain MRGO.
      The Robinson plaintiffs advance three arguments against applying the
DFE. First, they claim that the impact-review requirement of the National
Environmental Policy Act (“NEPA”) constituted a legal mandate that overrides
the Corps’s discretion. Next, they maintain that one or more project authoriza-
tions created a non-discretionary duty to armor the banks of MRGO. Finally,
they argue that the critical calculation made by the Corps in waiting to armor
MRGO was an erroneous scientific judgment, not a decision rooted in public-
policy considerations.



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                      Nos. 10-30249, 10-31054, 11-30808

                                    1. NEPA.
      NEPA mandates that “federal agencies must, except in certain qualifying
situations, complete a detailed environmental impact statement (‘EIS’) for any
major federal action significantly affecting the quality of the human environ-
ment.” O’Reilly v. U.S. Army Corps. of Eng’rs, 477 F.3d 225, 228 (5th Cir. 2007).
“An agency is not required to prepare a full EIS if it determines—based on a
shorter environmental assessment (EA)—that the proposed action will not have
a significant impact on the environment.” Winter v. Natural Res. Def. Council,
Inc., 555 U.S. 7, 16 (2008); see also 40 C.F.R. § 1508.9. If the federal action has
not been completed, agencies have an obligation to update an EIS by filing a sup-
plemental environmental impact statement (“SEIS”) if there are “significant new
circumstances or information relevant to environmental concerns and bearing
on the proposed action or its impacts.” 40 C.F.R. § 1502.9(c)(ii).
      The district court found (without challenge on appeal) that the Corps vio-
lated NEPA’s mandates in at least three ways:
      (1) [Its] 1976 []EIS was fatally flawed; (2) the Corps never filed a
      SEIS even after it acknowledged substantial changes caused by the
      maintenance and operation of the MRGO; and (3) it improperly seg-
      mented its reporting guaranteeing that the public and other agen-
      cies would remain uninformed as to the drastic effects the channel
      was causing.”

In re Katrina Canal Breaches, 647 F. Supp. 2d at 725. Though the court
acknowledged that “decisions to file EISs, SEISs and EAs are committed to the
judgment of the agency,” id. (citations omitted), it found the Corps had violated
NEPA under the standards of the Administrative Procedure Act: “[A] reviewing
court shall . . . hold unlawful and set aside agency action, findings, and conclu-
sions found to be . . . arbitrary, capricious, an abuse of discretion, or otherwise
not in accordance with the law,” 5 U.S.C. § 706.
      Even assuming the truth of those findings, however, NEPA is “a proce-


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                          Nos. 10-30249, 10-31054, 11-30808

dural, not substantive[,] environmental statute.” In re Katrina Canal Breaches,
647 F. Supp. 2d at 717. It is “‘now well settled that NEPA itself does not man-
date particular results, but simply prescribes the necessary process.’” City of
Shoreacres v. Waterworth, 420 F.3d 440, 450 (5th Cir. 2005) (quoting Robertson
v. Methow Valley Citizens Council, 490 U.S. 332, 350 (1989)). “Indeed, NEPA
does not prohibit the undertaking of federal projects patently destructive of the
environment; it simply mandates that the agency gather, study, and disseminate
information concerning the projects’ environmental consequences.” Sabine River
Auth. v. U.S. Dep’t of Interior, 951 F.2d 669, 676 (5th Cir. 1992).
      NEPA’s procedural mandates require agencies to inform their discretion
in decisionmaking. An agency that complies with NEPA gives outside influences
(the public, lawmakers, other agencies) more information with which to put pres-
sure on that agency, but the original agency retains substantive decisionmaking
power regardless. At most, the Corps has abused its discretionSSan abuse expli-
citly immunized by the DFE.


                               2. Duty to Armor MRGO.
      For their second attempt to negate the first DFE prong, the Robinson
plaintiffs allege that the Corps had a mandate from Congress to maintain
MRGO at a certain size: “The channel was to be 36 feet deep and 500 feet wide,
increasing at the Gulf of Mexico to 38 feet deep and 600 feet wide.” In re Katrina
Canal Breaches, 647 F. Supp. 2d at 702. But MRGO has now eroded to an aver-
age of three times its design width. Id. at 671.
      The district court recognized, however, that the design for MRGO
expressly contemplated erosion from wave wash and did not provide for armor-
ing the banks.5 The court held that these design features were “shielded by the

      5
          See In re Katrina Canal Breaches, 647 F. Supp. 2d at 654 (“‘No channel protection
                                                                              (continued...)

                                             17
                          Nos. 10-30249, 10-31054, 11-30808

[DFE],” id. at 702, a ruling that the plaintiffs do not challenge on appeal. Logi-
cally, therefore, the absence of armoring and the resultant erosion cannot have
violated a mandate sufficient to negate the first Berkovitz prong.


                             3. Delay in Armoring MRGO.
       In their attempt to negate the second DFE prong, the Robinson plaintiffs
allege that the critical calculation made by the Corps in waiting to armor MRGO
was an erroneous scientific judgment, not a decision rooted in public-policy con-
siderations. Under Berkovitz and Gaubert, the relevant question is whether the
discretionary judgment at issue involved the application of objective technical
principles or of policy considerations.6 If the discretion is “grounded in the policy
of the regulatory regime,” Gaubert, 499 U.S. at 325, the decision is immune
under the DFE, even if it also entails application of scientific principles. If it
involves only the application of scientific principles, it is not immune.
       For the government to enjoy DFE immunity, the deciding agent need not
have actually considered any policy implications; instead, the decision must only
be “susceptible to policy analysis.” Spotts, 613 F. 3d at 572. Under Gaubert, 499
U.S. at 324, “the very existence” of a law or regulation allowing a government
employee discretion (satisfying Berkovitz’s first prong) “creates a strong pre-
sumption that a discretionary act authorized by the regulation involves consid-


       5
         (...continued)
[was] included in the overall cost estimate of the project’” even though “‘erosion due to wave
wash in open areas [was] expected.’”) (quoting MRGO Design Memorandum 1-B (revised 1959)
¶19, at 5).
       6
         See Bear Medicine v. United States ex rel. Sec’y of Interior, 241 F.3d 1208, 1214 (9th
Cir. 2001) (stating that under Berkovitz, “actions based on technical or scientific standards are
not the kind of judgments meant to be protected from liability by the discretionary function
exception because those actions do not involve a weighing of policy considerations”); Ayala v.
United States, 980 F.2d 1342, 1349-51 (10th Cir. 1992) (applying Berkovitz and concluding that
“incorrect and inadequate” technical advice was not discretionary, because it involved “objec-
tive principles of electrical engineering”) (internal quotation marks omitted).

                                               18
                           Nos. 10-30249, 10-31054, 11-30808

eration of the same policies which led to the promulgation of the regulations.”
       That presumption can be overcome by specific facts about the actual bases
for the actor’s decision. See id. at 324-25. Therefore, FTCA plaintiffs can defeat
the presumption by showing, as a matter of fact, that the government’s actual
decision was not a policy-based one.7 That practice reflects the principle that,
although application of the exception turns on whether the decision is “suscepti-
ble to policy analysis,” id. at 325, “[e]vidence of the actual decision may be help-
ful in understanding whether the ‘nature’ of the decision implicated policy judg-
ments,” Cope v. Scott, 45 F.3d 445, 449 (D.C. Cir. 1995), in the first place.
       The Robinson plaintiffs and amici point to ample record evidence indicat-
ing that policy played no role in the government’s decision to delay armoring
MRGO. Amici AT&T Entities collected the most damning evidence in its sub-
mission to this court:
          The district court found as a matter of fact that, in operating,
       maintaining, and repairing the MRGO, the Corps labored under the
       mistaken scientific belief that the MRGO would not increase storm-
       surge risks. In a 1958 Design Memorandum, for example, the Corps
       stated that, “[f]or major storms and hurricanes when tides roll
       across the marsh many feet deep, as well as through the open water
       connections, the effect of the new [MRGO] channel will be of no con-
       sequence.” In 1966, the Corps used “rudimentary [scientific] model-
       ing” to analyze “whether there was indeed a funnel effect created by
       the [MRGO],” and concluded that “no additional surge was created
       by the [MRGO] funnel.”

         In subsequent years, as erosion widened the MRGO and increased
       its funnel effect, the Corps nevertheless hewed to its decades-old


       7
         See, e.g., Theriot v. United States, 245 F.3d 388, 399-400 (5th Cir. 1998) (per curiam)
(deciding whether the “government’s decision . . . was based on considerations of public policy”
based on the “underlying facts,” including “testimony” regarding what factors influence deci-
sions; applying the exception when that description was “not disputed by [plaintiffs]”); cf. Bal-
dassaro v. United States, 64 F.3d 206, 212 (5th Cir. 1995) (“[T]he burden is on [the plaintiff]
to allege facts that would support a finding that the challenged action is not the kind of conduct
that can be said to be grounded in the policy of the regulatory regime.”).

                                               19
                          Nos. 10-30249, 10-31054, 11-30808

      scientific judgment that “water levels . . . will not be higher” on
      account of the MRGO—notwithstanding “improved modeling tech-
      niques for storm surge” that demonstrated otherwise. [S]ee also
      AT&T Compl. ¶ 43 (citing scientific evidence that the Corps knew
      or should have known that the MRGO was a “superhighway” for
      storm surges and was described by a hurricane scientist as the
      “Crescent City’s Trojan Horse”). And because the Corps disbelieved
      the scientific evidence of the MRGO’s storm-surge effect, it did noth-
      ing to protect against it. See 647 F. Supp. 2d at 708 (finding that
      the Corps’ decisions were “grounded [in] its engineering position
      that the MRGO had no adverse effects with respect to storm surge”
      and assumptions that “any layperson, much less an engineer, could
      see” were false).[8]


      Amici’s account is confirmed by government counsel’s admissions in the
district court. In its motion to dismiss the Robinson complaint, the United
States explained that the Corps managed MRGO on the basis of its flawed scien-
tific knowledge: “Because [the Corps] thought that the new channel [would] be
of no consequence in affecting water surface elevations for major storms and hur-
ricanes,” MRGO “was constructed with no barriers or other means to slow down
storm-driven surges.” At oral argument in the district court, the United States
made the same admission: The Corps “determined that MRGO played no role
in major hurricane events” and, “for that reason, the Corps saw no reason” to
take any steps to remedy MRGO’s dangers. In re Katrina Canal Breaches, 577
F. Supp. 2d at 815.
      Against the considerable evidence amassed to suggest that the Corps’s
decisions were grounded on an erroneous scientific judgment, not policy consid-
erations, the government offers little affirmative evidence: “[I]n the Corps’ view,
maintaining MR-GO through dredging and raising the levees through separate
projects allowed the Corps to maximize its limited resources and to continue
operating the MR-GO as a shipping channel as Congress charged it to do.” This

      8
          Some of amici’s citations have been omitted.

                                             20
                       Nos. 10-30249, 10-31054, 11-30808

quotation is the closest the government comes to arguing that it had policy
reasons—and not faulty scientific ones—for delaying MRGO’s armoring. But the
government’s contention cannot stand where there is no record evidence that,
because of budgetary constraints, the Corps failed to implement feasible reme-
dial measures or that it ever performed a cost-benefit analysis. “Here, there was
no balancing or weighing of countervailing considerations.” In re Katrina Canal
Breaches, 647 F. Supp. 2d at 732.
      The Robinson plaintiffs have mustered enough record evidence to demon-
strate that the Corps’s negligent decisions rested on applications of objective sci-
entific principles and were not susceptible to policy considerations. At points
where it could have mattered, the Corps did not identify MRGO’s ability to
aggravate the effect of a major hurricane. This is not a situation in which the
Corps recognized a risk and chose not to mitigate it out of concern for some other
public policy (e.g., navigation or commerce); it flatly failed to gauge the risk.
Accordingly, the DFE is inapplicable to the Robinson plaintiffs’ claims.


       B. Applying the DFE to the Corps’s Dredge Permitting Process.
      The Anderson plaintiffs do not fare as well. In their motion to dismiss,
they rely on the following regulation:
      § 320.4 General policies for evaluating permit applications.

      (a) Public interest review.

      (a)(1) The decision whether to issue a permit will be based on an
      evaluation of the probable impact including cumulative impacts of
      the proposed activity and its intended use on the public interest.
      Evaluation of the probable impact which the proposed activity may
      have on the public interest requires a careful weighing of all those
      factors which become relevant in each particular case. The benefits
      which reasonably may be expected to accrue from the proposal must
      be balanced against its reasonably foreseeable detriments. The
      decision whether to authorize a proposal, and if so, the conditions

                                         21
                         Nos. 10-30249, 10-31054, 11-30808

       under which it will be allowed to occur, are therefore determined by
       the outcome of the general balancing process. That decision should
       reflect the national concern for both protection and utilization of
       important resources. All factors which may be relevant to the pro-
       posal must be considered including the cumulative effects thereof:
       among those are conservation, economics, aesthetics, general envir-
       onmental concerns, wetlands, cultural values, fish and wildlife val-
       ues, flood hazards, flood plain values, land use, navigation, shore
       erosion and accretion, recreation, water supply and conservation,
       water quality, energy needs, safety, food and fiber production, min-
       eral needs and, in general, the needs and welfare of the people. No
       permit will be granted unless its issuance is found to be in the pub-
       lic interest.[9]

       The Anderson plaintiffs argue that the Corps’s issuance of dredging per-
mits for the 17th Street Canal fails both prongs of the Berkovitz test. Prong one,
they contend, is not met, because the regulation imposes a “non-discretionary
duty” on what the Corps does; it is “replete with language couched in mandatory
terms such as ‘will,’ ‘must,’ ‘requires,’ ‘determined,’ and ‘should,’” with such
terms’ being included in almost every sentence. Prong two, they contend, is not
met, because the regulation implicates matters of scientific judgment.
       The argument fails on both tries. The regulation “leaves it to a federal
agency or employee to determine when and how to take action,” meaning that
the Corps had discretion, satisfying prong one; “the ostensibly mandatory lan-
guage,” “when read in light of the broad goals” of the regulation, allowed for the
exercise of judgment and choice. Freeman, 556 F.3d at 337, 338 (citation omit-
ted). The regulation instructed the Corps to consider several factors, some tech-
nical (e.g., shore erosion and accretion) but also many that concern policy (sum-
marized by the catch-all “needs and welfare of the people”), satisfying prong two
as well. The DFE is applicable to the Anderson plaintiffs, because the Corps’s


       9
        33 C.F.R. § 320.4(a)-(a)(1) (1984). The regulation quoted is the version in effect in
1984. It has since changed in ways not relevant to this litigation.

                                             22
                        Nos. 10-30249, 10-31054, 11-30808

action under the regulation satisfies both prongs of the Berkovitz test.


                           V. Robinson Cross-Appeals.
      Four Robinson plaintiffs cross-appeal the ruling that the Corps is not lia-
ble for some or all of the flooding that destroyed their homes. We review their
legal arguments de novo and their factual arguments under the deferential
clear-error standard.


                               A. The Robinsons.
      Norman and Monica Robinson, who reside within the New Orleans East
polder, claim that MRGO created a “funnel effect” that increased the power of
Hurricane Katrina’s storm surge, such that the Reach 1 Levee was breached and
the Citrus Back Levee was overtopped, exacerbating the flooding of their house.
They also contend that the Corps should have installed a surge barrier, which
would have prevented any significant flooding in New Orleans East. In re
Katrina Canal Breaches, 647 F. Supp. 2d at 696. They contend that the Corps
was negligent in its maintenance and operation of MRGO and its failure to cre-
ate a surge protection barrier.
      The district court found that the Corps permissibly relied on the “Bret-
schneider and Collins Report,” which stated that MRGO’s effect on storm surge
would generally be minimal. Id. Therefore, the court reasoned, “a duty did not
exist to construct a surge protection barrier,” and the Corps was not negligent
for failing to construct the barrier or for the effects of a widened MRGO. Id.
at 697. In addition, the court found that the complained-of “funnel effect” would
have been present in MRGO’s initial design and construction, meaning the Corps
cannot be held liable for the plaintiffs’ damages because of the DFE. Id.
      Plaintiffs contend that the court erred in finding that the Corps reasonably
relied on the Bretschneider and Collins report, because later studies called it

                                       23
                       Nos. 10-30249, 10-31054, 11-30808

into question, a fact allegedly ignored by the district court. More specifically, the
plaintiffs contend that though the Corps may have reasonably relied on the
report when it was released, it was unreasonable to rely on it for the next thirty
years while new reports came out calling its conclusions into question.
      Despite these contentions, the court did not clearly err in finding that the
Corps was reasonable in relying on the report. Contrary to the plaintiffs’ conten-
tions, the court did consider the later reports but still found that the Corps’s
actions were reasonable and that it had no duty to erect a storm surge barrier.
See id. at 696-97. Moreover, there were several later studies and occurrences
that supported the Bretschneider and Collins report’s conclusions, including a
2003 Corps study and the experience of Hurricane Camille. Id. at 678. Thus, the
district court did not commit clear error when it determined that the Corps had
no duty to construct a storm surge barrier based on its reasonable reliance on
the report, both when it was issued and in later decades.
      In addition to these arguments, however, the Robinsons urge that the
maintenance of MRGO itself, regardless of the installation of a surge barrier,
worsened the flooding of their area by an additional six feet of water, on top of
the six feet that would have been there anyway. The district court did not con-
sider that distinct theory of liability in a separate section, but its findings imply
that it considered and rejected the negligent-maintenance theory as well.
      The court intertwined its ruling on the surge-protection barrier with its
ruling on the maintenance issue. The court called attention to the fact that, had
MRGO remained at its original dimensions through proper maintenance, its
original design would have caused the Robinsons’ property to suffer six feet of
flooding regardless. “This fact indicates that a substantial portion of the harm
would have arisen from the original design and presents substantial causation
issues which will not be discussed based on the Court’s finding of no negligence.”
Id. at 697. If harm from the original design were legally actionable, then, it

                                         24
                       Nos. 10-30249, 10-31054, 11-30808

would present a substantial causation issue only if it were mixed with another
harm the court found non-actionable, namely, the added flooding caused by the
widened MRGO. The Robinsons have not shown that the court clearly erred in
rejecting their negligent-maintenance argument.


                               B. The Franzes.
      The Franzes, who lived in the St. Bernard polder, allege that the Corps’s
negligent maintenance of MRGO caused the destruction of their home via the
breach of the Reach 2 Levee. The district court found that the Corps was negli-
gent in maintaining MRGO, which caused the breach of the Reach 2 Levee and
the destruction of many homes in the polder. Id. The court found, however, that
the Franzes’ home was destroyed by flooding from the breaches in the Inner Har-
bor Navigation Canal (“IHNC”) floodwall (not caused by the Corps’s negligence
in maintaining MRGO), not by floodwater from the Reach 2 Levee breach, which
reached the Franzes’ home some time later. Id. at 735. But, the court found,
“without the Reach 2 Levee breaching, the second floor would have not been
flooded and the majority of the contents would not have been damaged.” Id. It
therefore awarded damages for the loss of possessions on the second floor but not
for the loss of the house.
      The Franzes challenge the award by arguing that the court erred in find-
ing that their home was destroyed by the IHNC waters. Claiming their evidence
was unrebutted, they maintain that it was the Reach 2 waters that destroyed
the foundation of the house, and the combination of the two waters standing still
for three weeks destroyed its structure. The Franzes rely on the fact that when
concurrent causes are responsible for damage, Louisiana law shifts the burden
to the defendant to show which harms did not result from his actions.
      As plaintiffs’ argument acknowledges, however, the burden of proof shifts
only if they can show that the Reach 2 waters were a cause-in-fact of their harm.

                                       25
                          Nos. 10-30249, 10-31054, 11-30808

Under Louisiana law, the Reach 2 waters were a cause-in-fact of the damages
if they were a substantial factor in destroying the house.
       There can be more than one cause-in-fact of an accident as long as
       each cause bears a proximate relation to the harm that occurs and
       it is substantial in nature. A plaintiff seeking to recover . . . must
       prove that the negligent act or defect complained of was a cause-in-
       fact of the injury.

Rando v. Anco Insulations Inc., 16 So. 3d 1065, 1088 (La. 2009).
       The district court found the house already destroyed by the earlier arrival
of the IHNC floodwaters. In re Katrina Canal Breaches, 644 F. Supp. 2d at 735.
Several feet of IHNC waters reached the house 30 to 120 minutes before the
Reach 2 waters. Not only did that initial onslaught of water damage the house,
but the IHNC waters also could have been responsible for a large object’s collid-
ing with it and damaging the foundation.10 Although the Franzes argued the
house was destroyed by the stagnation of the combined MRGO and IHNC wat-
ers, our review for clear error is highly deferential to findings of fact. In light of
the evidence described above, the finding that the initial floodwaters destroyed
the house is not clearly erroneous. The Franzes have thus failed to establish
that MRGO’s floodwaters were a cause-in-fact of the destruction.


                      VI. The Armstrong Trial: No Mandamus.
       The government petitions for a writ of mandamus to stay proceedings in
Armstrong v. United States, No. 10-866 (E.D. La.), pending this court’s disposi-
tion of Robinson. The government had originally requested action on its petition
by September 2011, but a motions panel of this court denied an initial stay and
consolidated the petition for oral argument with Robinson and Anderson.



       10
         The plaintiffs failed to demonstrate that the object crashed into the house as a result
of the Reach 2 waters rather than the IHNC waters.

                                              26
                        Nos. 10-30249, 10-31054, 11-30808

      To decide whether to stay the Armstrong trial by the extraordinary writ
of mandamus, we must decide whether the petitioner has satisfied three require-
ments: (1) The “party seeking issuance of the writ [must] have no other ade-
quate means to attain the relief he desires—a condition designed to ensure that
the writ will not be used as a substitute for the regular appeals process”; (2) “the
petitioner must satisfy the burden of showing that [his] right to issuance of the
writ is clear and indisputable”; and (3) “even if the first two prerequisites have
been met, the issuing court, in the exercise of its discretion, must be satisfied
that the writ is appropriate under the circumstances.” Cheney v. U.S. Dist.
Court, 542 U.S. 367, 380-81 (2004) (alterations in original) (internal quotation
marks omitted).
      Even under the dubious assumption that the government could meet the
first and third prerequisites, its petition founders on the second. We affirm all
the rulings on immunity, save for a minor reformulation of FCA immunity.
Because we do not alter the scope of governmental immunity in any way likely
to affect the Armstrong case, the government has no clear and indisputable right
to issuance of the writ. Accordingly, we deny the petition.


                                  VII. Conclusion.
      The district court’s careful attention to the law and even more cautious
scrutiny of complex facts allow us to uphold its expansive ruling in full, except-
ing our minor restatement of FCA immunity.11 Accordingly, we AFFIRM the
judgments in Robinson and Anderson, leaving each party as he was before this
appeal. Similarly, we DENY the government’s petition for a writ of mandamus
to stay the Armstrong trial.



      11
        Because we find the government immune in Anderson, we decline to reach its argu-
ment that the plaintiffs failed to state a claim under Louisiana tort law.

                                          27
