FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

LORI OBERSON, Legal Guardian for 

Brian Musselman, an incapacitated

person; KIMBERLEE MUSSELMAN,

individually and as the Natural

Mother of Devon Musselman, a

minor,

Plaintiffs-AppelleesCross-Appellants,

v.

UNITED STATES DEPARTMENT OF

AGRICULTURE, FOREST SERVICE, Nos. 04-35268

Defendant-Third-Party 04-35315

Plaintiff-Appellant- D.C. No.

Cross-Appellee,  CV-99-00048-DWM

and OPINION AND

STATE OF MONTANA, by and ORDER

through the Department of Fish,

Wildlife and Parks; WEST

YELLOWSTONE CHAMBER OF

COMMERCE,

Defendants-ThirdParty Plaintiffs,

v.

JAMIE LOUIS LEINBERGER; PATRICK

B. KALAHAR; TIM A. JOHNSON,

Third-Party Defendants. 

Appeal from the United States District Court

for the District of Montana

Donald W. Molloy, District Judge, Presiding

2865
Argued and Submitted

December 7, 2005—Seattle, Washington

Filed March 20, 2006

Before: Ronald M. Gould and Marsha S. Berzon,

Circuit Judges, and William W Schwarzer,*

Senior District Judge.

Opinion by Judge Schwarzer

*The Honorable William W Schwarzer, Senior United States District

Judge for the Northern District of California, sitting by designation. 

2866 OBERSON v. USDA
OPINION AND ORDER

SCHWARZER, Senior District Judge: 

I. CERTIFICATION OF QUESTIONS OF LAW

Pursuant to Rule 44(c) of the Montana Rules of Appellate

Procedure, we respectfully request the Montana Supreme

Court to exercise its discretion to adjudicate the following

questions of Montana law: 

1. Does the gross negligence standard of care in the

snowmobile liability statute, MONT. CODE ANN. § 23-2-653

(1996), violate the Montana equal protection clause, MONT.

CONST. art. II, § 4? 

OBERSON v. USDA 2869
2. If the snowmobile liability statute’s gross negligence

standard is unconstitutional, does the recreational use statute’s

willful or wanton misconduct standard of care, MONT. CODE

ANN. § 70-16-302(1) (1996), apply in its place? 

3. If neither the snowmobile liability statute nor the recreational use statute provide an applicable standard of care, does

the ordinary care standard, MONT. CODE ANN. § 27-1-701,

apply? 

The answers to the certified questions will be determinative

of the appeal pending in our court in this action. We have

found no controlling Montana appellate decisions, constitutional provisions, or statutes for these questions. We acknowledge that your Court may decide to reformulate the questions,

and that our phrasing of the questions is not intended to

restrict your Court’s consideration of this request. Relevant

facts concerning the certified questions are stated below. We

would be grateful for any guidance your Court can give us,

whether or not directly responsive to the questions as we have

phrased them. 

II. PROCEDURAL BACKGROUND

Brian Musselman (Musselman) was gravely injured in a

snowmobile accident on a National Forest trail. Lori Oberson,

his legal guardian, and others brought this action against the

United States under the Federal Tort Claims Act (FTCA), 28

U.S.C. §§ 2671-2680, alleging that the United States Forest

Service negligently failed to correct or warn of a dangerous

condition on the Big Sky snowmobile trail where Musselman

was injured. The United States filed a third-party complaint

against Jamie Leinberger (Leinberger), Patrick Kalahar (Kalahar) and Tim Johnson (Johnson), alleging that their negligence caused Musselman’s injuries. Default was taken against

Johnson. Kalahar settled with plaintiffs and was dismissed

before trial. Following a bench trial, the district court entered

judgment for plaintiffs, awarding damages of $11,296,800

2870 OBERSON v. USDA
and apportioning liability 40% to the Forest Service, 50% to

Leinberger and 10% to Musselman.1

The Forest Service appealed, citing as error the district

court’s refusal to apply the discretionary function exception of

the FTCA and its finding of negligence. Plaintiffs crossappealed from the district court’s liability allocation of 50%

to third-party defendants and its methodology for calculating

life expectancy.2 We affirm the district court in all respects

except that we leave for future resolution the determinative

question of the appropriate standard of care pending the disposition of this request for certification. 

1The opinion of the district court is reported at 311 F. Supp. 2d 917 (D.

Mont. 2004). 

2Plaintiffs advance three contentions on their cross-appeal. We find

each to be without merit. 

First, they contend that the district court erred in holding Kalahar and

Leinberger jointly and severally liable for Musselman’s injuries and

thereby apportioning 50% of the liability to Leinberger, the remaining

tortfeasor. The court correctly rejected plaintiffs’ argument that a meeting

of the minds had to be proved to establish joint and several liability, relying on the leading case of Summers v. Tice, 199 P.2d 1 (Cal. 1948), which

held that where two tortfeasors are each negligent but it cannot be determined whose negligence was the actual cause of the injuries, each is liable

for the entire damage. See Azure v. City of Billings, 596 P.2d 460, 470

(Mont. 1979) (citing Tice, 199 P.2d 1). 

Second, they contend that the district court violated the “empty chair”

rule by factoring Kalahar’s negligence in the allocation of 50% liability to

Kalahar and Leinberger. The court, however, specifically acknowledged

that no liability can be apportioned to a defendant who has settled and

allocated liability solely to Leinberger. See Azure, 596 P.2d at 469. 

Third, they contend that the district court erred in accepting the Forest

Service’s expert’s estimate of Musselman’s life expectancy, which did not

take into account the quality of medical care provided to Musselman. The

court’s life expectancy finding is a finding of fact reviewed for clear error.

The finding was supported by substantial evidence and has not been

shown to be clearly erroneous. Sines v. United States, 430 F.2d 644, 645

(9th Cir. 1970). 

OBERSON v. USDA 2871
III. FACTS

A. THE ACCIDENT

On February 25, 1996, Musselman, an expert snowmobiler,

joined friends to ride on snowmobile trails in Yellowstone

National Park and Gallatin National Forest. After dark, Musselman and his friends rode to a restaurant some nine miles

north of West Yellowstone, Montana. Musselman, joined by

Kalahar, Johnson, and Leinberger, rode on the Big Sky Trail,

a groomed snowmobile trail managed by the U.S. Forest Service. During the trip, Johnson and Kalahar were riding competitively at speeds up to 60 mph. 

At the restaurant, Musselman and his friends joined a group

of some twenty people to cook steaks, drink beer, and tell stories. Musselman and Kalahar each drank at least three beers,

Johnson consumed three to four beers, and Leinberger consumed between four and eight beers. Upon leaving the restaurant around 10:00 p.m., Leinberger was heavily impaired by

alcohol, Johnson and Kalahar were impaired to a lesser

degree, and Musselman was not impaired and was fully able

to operate his snowmobile. 

Musselman and Johnson left the restaurant first, followed

by Kalahar and Leinberger. No member of the group had previously traveled on the stretch of the Big Sky Trail immediately adjacent to the restaurant. The Forest Service had posted

a speed limit of 45 mph on its Yellowstone-area trails, but

was aware that snowmobilers regularly traveled this stretch of

trail at speeds in excess of 60 mph. Musselman took off

quickly from the restaurant and continued at a pace keeping

him in front of the other riders. He was not exceeding 45 mph

when he reached the accident site. Johnson, Kalahar, and

Leinberger approached the accident site at approximately 50-

55 mph. 

The stretch of trail approaching the accident site is flat and

smooth for roughly a quarter of a mile. It then drops suddenly

2872 OBERSON v. USDA
down a steep hill, the site of the accident. There it loses seventeen feet of elevation over approximately eighty feet, an

11.5 degree pitch or 25% slope. Musselman was the first rider

to come to the hill, negotiating it safely and landing his snowmobile under control slightly off the trail. Johnson was next

over the hill, crashing his machine at the bottom. After Johnson’s crash, Musselman got off his machine for reasons

unknown, although the district court found that he was likely

trying to help Johnson or warn the approaching riders of the

drop. As Musselman stepped on the trail, Kalahar and Leinberger came flying over the hill side-by-side. One of the riders hit Musselman’s head, causing catastrophic brain injuries.

The injury left Musselman unable to swallow, speak, understand complex communication, and independently conduct

activities of daily living. He currently resides in an adult care

facility. 

The court had difficulty reconstructing the scene immediately following the accident given the shambolic postaccident investigation.3

 However, it found that Musselman

was lying on the groomed portion of the trail between his and

Leinberger’s machine, with his head facing away from the

hill. Leinberger’s machine was still on the groomed trail with

its front end, windshield, handlebars, tunnel area, skis, cowling, rear bench rest, and motor mounts damaged. Kalahar’s

machine suffered broken engine mounts, a damaged windshield, and bent handlebars. Johnson’s machine had a damaged windshield, which he replaced the morning after the

accident before the machine could be inspected. 

There were no eyewitnesses to the accident. Leinberger testified that he did not believe he hit Musselman because he

3The investigators lost notes they had taken that night, took only two

photographs of the scene, did not prevent the snowmobiles from being

moved, spoiled the blood sample drawn from Musselman the night of the

accident, and did not order blood drawn from the other riders involved in

the accident. 

OBERSON v. USDA 2873
“didn’t hit an object that was going to move.” Kalahar testified that he was positive he did not hit Musselman. Physical

evidence and attempts at reconstruction revealed only that a

snowmobile track hit Musselman in the helmet while he was

on the trail and that the impact came from the right to left

side. 

Plausible explanations can be given for either Leinberger or

Kalahar hitting Musselman. Leinberger’s machine tumbled

after the crest of the hill either because he applied his brakes

before becoming airborne or because he hit Musselman while

airborne, forcing the nose of his snowmobile down. Alternatively, the line of travel for Kalahar’s machine places it in line

with Musselman’s likely location at the moment of the accident. Additionally, Kalahar reported hitting the ground and

bouncing, an account consistent with hitting Musselman and

then hitting the ground. 

B. THE TRAIL

Musselman’s accident occurred at a sudden and steep drop

on the Big Sky Trail. At the time of the accident, there were

no signs warning of the hill or instructing riders to slow down.

Numerous witnesses suggested at trial that it was unusual for

such a drop not to be signed and that a trail of such abrupt

steepness was rare. 

The Forest Service has sole responsibility for identifying

and correcting hazards on the Big Sky Trail. To identify hazards, the Forest Service engages in a process called “warranting.” The program manager for the Gallatin National Forest

described the process as “identifying the hazards that our

average, prudent, reasonable rider would not expect based on

a spectrum of users that we had out there.” Forest Service

employees identify hazards during warranting by riding the

trail at 35 mph during the day. Upon identifying a hazard, the

Forest Service closes the trail, corrects the hazard, or warns

the user. The Forest Service does not warrant trails at night,

2874 OBERSON v. USDA
on the assumption that reflectors and a rider’s judgment as to

the appropriate speed will provide sufficient protection. 

The Forest Service originally warranted the Big Sky Trail

in 1993, at which point it did not identify the hill as a hazard.4

The speed limit at the site of the accident, as on all other trails

in the region, was then 35 mph. A month before the accident,

the Forest Service implemented a new speed limit of 45 mph

solely for consistency with the speed limit in effect in adjacent Yellowstone National Park. The Forest Service did not

warrant the trails at 45 mph. 

Sixteen days before Musselman’s accident, two snowmobiles and a snow grooming machine were involved in an accident at the hill in question. The snowmobiles were traveling

in clear weather at night, going 35-40 mph, which the investigation report characterized as too fast based upon the conditions. The two snowmobiles collided with the grooming

machine immediately after coming over the crest of the hill.

In a Forest Service re-creation following the accident, an

observer 100 feet back from the hill could not see the grooming machine, equipped with two headlights and a flashing

light on top, when it was at the bottom of the hill. Although

the collision caused only minor damage to the involved

machines and no personal injury, the district court found that

the accident could have resulted in serious injury to the riders.

C. THE DISTRICT COURT DECISION

The district court held that the Forest Service’s decisions

whether to warrant the trails and how it would conduct the

4Following the accident, in November 1996, the Forest Service rewarranted the trail, making several adjustments to the site of the accident. The

Service realigned the approach to the hill, replacing the straight, flat

approach with a curve leading through trees. Additionally, signs were

added indicating the upcoming curve and subsequent hill. The warranting

form also noted that the hill can “sneak up on a person” at night and that

the hill’s crown was scheduled for reduction. 

OBERSON v. USDA 2875
process were grounded in policy considerations and were the

type of discretionary decisions Congress intended to shield

from tort liability. Once the decision to warrant the trails was

made, however, the agency had a duty to accomplish that task

with reasonable care. The Service’s failure to warn of the hazardous hill was not the result of a decision grounded in public

policy or of a choice among competing policy considerations.

The court concluded that the Forest Service’s failure to correct or warn of this hazard was not the type of discretionary

decision that is shielded from tort liability. 

Having determined that the plaintiffs could sue the Forest

Service, the district court considered whether the Service

owed them a duty under Montana law. It held that the existence of a duty was not negated by the Montana snowmobiling statutes relieving parties of liability for risks “inherent in

the sport of snowmobiling.” MONT. CODE ANN. §§ 23-2-651,

653-54 (1996). The hill, it found, was not an inherent risk as

a “variation in terrain” because the Forest Service had notice

of the danger and could have eliminated it with ordinary care

by altering the trail and/or posting a warning. 

The court then addressed the applicable standard of care.

First, it held the Montana snowmobile liability statute’s gross

negligence standard, MONT. CODE ANN. § 23-2-653(2) (1996)

(amended 1997), to be unconstitutional under Montana’s

equal protection clause, MONT. CONST. art. II, § 4, on the

authority of Brewer v. Ski-Lift, Inc., 762 P.2d 226 (Mont.

1988). Next, the court declined to apply Montana’s recreational use statute in its place, holding the statute’s willful or

wanton misconduct standard, MONT. CODE ANN. § 70-16-

302(1), to be preempted in this instance by the more specifically applicable snowmobile liability statute. In the absence of

other applicable standards, the court imposed a duty of ordinary care. The court found the ordinary care standard, adopted

in the 1999 revision of the snowmobile statute in place of the

gross negligence standard, to be constitutional. Finally, the

district court held that the Forest Service breached its duty of

2876 OBERSON v. USDA
ordinary care to plaintiffs and that the breach contributed to

Musselman’s injuries. 

The court next considered whether any of the other parties

shared responsibility for the accident. It concluded that Musselman exposed himself to severe injury by walking onto the

trail and, further, that Leinberger and Kalahar, given their

speed and alcohol-impaired state, and the evidence of contact

with Musselman, breached their duty to avoid injury to others.

Since it proved impossible to determine whether it was Leinberger or Kalahar who hit Musselman, the court held both

jointly and severally liable for Musselman’s injuries. 

The court apportioned 40% of the liability to the Forest

Service, 10% to Musselman, and 50% to Kalahar and Leinberger. Since Kalahar had settled with Musselman and been

dismissed from the suit as a result of his settlement with Musselman, the court assigned the 50% share of liability solely to

Leinberger on the ground that he and Kalahar had acted in

concert. In calculating damages, the district court used a

future life expectancy of 12.8 years. After reducing the

amount by 10% for Musselman’s liability, the court entered

judgment for plaintiffs in the amount of $10,167,120. 

IV. DISCUSSION

A. FTCA’s DISCRETIONARY FUNCTION

EXCEPTION

[1] The United States “can be sued only to the extent that

it has waived its immunity.” United States v. Orleans, 425

U.S. 807, 814 (1976). The FTCA waives the federal government’s immunity from suit for a discrete class of lawsuits. 28

U.S.C. §§ 2671-80 (2005). This waiver, however, is limited

by the discretionary function exception, precluding “[a]ny

claim based upon an act or omission of an employee of the

Government . . . based upon . . . a discretionary function or

duty.” 28 U.S.C. § 2680(a). The Supreme Court has estabOBERSON v. USDA 2877
lished a two-part test for application of the discretionary function exception. See United States v. Gaubert, 499 U.S. 315,

322-25 (1991); Berkovitz v. United States, 486 U.S. 531, 536-

37 (1988). First, courts inquire as to whether the challenged

action was discretionary, as opposed to being governed by

mandatory statute, policy, or regulation. Whisnant v. United

States, 400 F.3d 1177, 1180-81 (9th Cir. 2005) (summarizing

Berkovitz test). Second, if the court finds the action to have

been discretionary, it then determines whether the action

involved “a decision susceptible to social, economic, or political policy analysis.” Id. at 1181; see also O’Toole v. United

States, 295 F.3d 1029, 1033-34 (9th Cir. 2002). If the challenged action was both discretionary and policy driven, the

discretionary function exception bars FTCA claims. We

review de novo the district court’s application of the discretionary function exception. Marlys Bear Med. v. United

States, 241 F.3d 1208, 1213 (9th Cir. 2001). 

[2] There is no serious claim that the Forest Service’s

actions in this case were mandated by statute, policy or regulation. The question is whether its discretionary actions were

policy driven. The Forest Service argues that the absence of

a warning sign at the hill was the direct result of the 1993

warranting process protected by the discretionary function

exception. But as the Forest Service’s brief explains, the warranting process was conducted at a route design speed of 35

mph and did not identify the hill as a hazard. Later, in 1996,

the Service raised the speed limit to 45 mph—the limit in

effect at the time of the accident—simply to conform to the

speed limit in Yellowstone Park, resulting in the creation of

the hazardous condition at the hill. Because the trails were

never warranted at the higher speed limit of 45 mph, the Service is not shielded by the warranting process. 

[3] The Service’s argument that the decision not to rewarrant the trails in 1996 was protected by the discretionary function exception misses the point. Undoubtedly, its decision

whether to warrant trails is protected, as is its decision to

2878 OBERSON v. USDA
adopt a 45 mph speed limit. But not having warranted the

trails at 45 mph, the Service cannot claim that its failure to

warn of hazardous conditions at that speed is protected by the

discretionary function exception. 

[4] Inasmuch as the warranting process does not shield the

Service under the circumstances of this case, we must consider whether the failure to post a warning at the hill is protected by the discretionary function exception. Whether it is

protected depends on whether the Service’s action—or

inaction—was grounded in social, economic or political policy. Other than its (misplaced) reliance on the 1993 warranting process, the Service offers no evidence to show that its

failure to post a warning was the result of a policy decision.

This case is not like Childers v. United States, 40 F.3d 973

(9th Cir. 1995), where the decision not to post signs and to

close portions of Yellowstone National Park were the result

of policy decisions regarding how best to manage the park

during winter. The court explained: 

Unable to maintain all the trails in the park, cognizant that posting warning signs would inadvertently

attract visitors to unmaintained trails, and unable to

post signs throughout the park, NPS could only

decide to close large portions of the park, or to keep

the park open, provide visitors with information on

the hazards, and take steps to discourage visitors

from going to hazardous areas. 

Id. at 976. Similarly, in Valdez v. United States, 56 F.3d 1177

(9th Cir. 1995), the failure to install warning signs alongside

a potentially hazardous stream was held to “implicate[ ] a

choice between the competing policy considerations of maximizing access to and preservation of natural resources versus

the need to minimize potential safety hazards.” Id. at 1180;

see also Blackburn v. United States, 100 F.3d 1426, 1434 (9th

Cir. 1996) (following Valdez and Childers, holding the decision how to warn public of the hazard of diving off a bridge

OBERSON v. USDA 2879
in Yosemite National Park involved considerations of visitor

enjoyment, preservation of historical features, minimizing

manmade intrusions and protection of wildlife and the environment). 

[5] The case before us is different. It is more nearly analogous to cases such as Summers v. United States, 905 F.2d

1212, 1215-16 (9th Cir. 1990), holding the discretionary function did not protect the Park Service where it had failed to

warn visitors of the danger of stepping on hot coals in a fire

ring in the Golden Gate National Recreation Area. The court

found that “NPS’s failure to identify and warn of the danger

to barefoot visitors of hot coals on park beaches resembles

more a departure from the safety considerations established in

Service policies . . . than a mistaken judgment in a matter

clearly involving [policy] choices.” Id. at 1216. Similarly,

Faber v. United States, 56 F.3d 1122, 1127 (9th Cir. 1995),

held that the Forest Service’s failure to post a sign warning of

danger of diving off a waterfall in a National Forest was not

protected by the discretionary function exception. The court

stated: “It would be wrong to apply the discretionary function

exception in a case where a low-level government employee

made a judgment not to post a warning sign . . . .” Id. at 1125;

see also Seyler v. United States, 832 F.2d 120, 123 (9th Cir.

1987) (stating “we doubt that any decision not to provide adequate signs would be of the nature and quality that Congress

intended to shield from tort liability”) (internal quotation

marks and citation omitted). In Sutton v. Earles, 26 F.3d 903,

910 (9th Cir. 1994), the court held the Navy’s decision not to

post speed limit signs after creating a hazard to navigation not

protected by the discretionary function exception, stating that

“[a] decision not to warn of a specific, known hazard for

which the acting agency is responsible is not the kind of

broader social, economic or political policy decision that the

discretionary function exception is intended to protect.” Here,

the Forest Service knew of the hazard through its own investigation, which disclosed that sixteen days prior to Musselman’s accident the hill in question had been the site of a

2880 OBERSON v. USDA
potentially serious collision between a snow grooming

machine and two snowmobiles. In the absence of any evidence that the failure to post a warning or remedy the hazard

was the product of a policy choice, we conclude that the discretionary function exception did not shield the Forest Service

from liability. 

B. THE GOVERNMENT’S NEGLIGENCE 

“A negligence action requires proof of four elements: (1)

existence of a duty; (2) breach of the duty; (3) causation; and

(4) damages.” Gentry v. Douglas Hereford Ranch, Inc., 962

P.2d 1205, 1209 (Mont. 1998).5 The district court addressed

the four elements required for a negligence action. In holding

that the government had breached its duty to Musselman, the

district court applied a standard of ordinary care under Montana law. As we discuss later in this order, the government

disputes the application of that standard, contending that the

standard is either gross negligence or willful or wanton misconduct. Because we leave this issue for determination by the

Montana Supreme Court by way of this certification, we defer

its resolution pending a response from that Court. However,

our order resolves all other issues and leaves only the standard

of care as determinative of this appeal. 

1. The Government’s Duty

a. Inherent risk 

[6] To establish a claim of negligence, a plaintiff must first

demonstrate the existence of a duty of care. Gaudreau v. Clinton Irrig. Dist., 30 P.3d 1070, 1073 (Mont. 2001). “The existence of a legal duty can be determined as a matter of law.”

Lopez v. Great Falls Pre-Release Servs., Inc., 986 P.2d 1081,

1087 (Mont. 1999). The Forest Service owed a duty of care

to all persons which it could reasonably foresee would use the

5The Forest Service does not dispute the trial court’s damage award. 

OBERSON v. USDA 2881
snowmobile trail. Id.; see Busta v. Columbus Hosp. Corp.,

916 P.2d 122, 134 (Mont. 1996) (“Duty . . . is measured by

the scope of the risk which negligent conduct foreseeably

entails” (quoting Mang v. Elaisson, 458 P.2d 777, 781-82

(1969)). 

The government argues that Musselman cannot show the

existence of a duty because Montana’s snowmobile statute

places all legal responsibility for risks “inherent in the sport

of snowmobiling” on the snowmobiler. MONT. CODE ANN.

§ 23-2-654 (1996). It argues that the statute relieved the government of liability for the failure to warn Musselman of the

“variation in terrain” on which he was injured. § 23-2-654(1).

The government, however, overstates the law. 

[7] We review de novo a district court’s interpretation of

state law. See Rabkin v. Or. Health Scis. Univ., 350 F.3d 967,

970 (9th Cir. 2003). To determine whether the government

had a duty to warn Musselman of the hill’s hazardous nature,

we must interpret the meaning of “inherent risk” in the Montana snowmobile statute. Courts considering the meaning of

“inherent risk” or similar language in similar statutes have

held that language to shield defendants from liability for risks

that are integral parts of a sport and, therefore, could not be

eliminated by a defendant with ordinary care. See Brewer v.

Ski-Lift, Inc., 762 P.2d 226, 231 (Mont. 1988); see also Bouchard v. Johnson, 555 N.W.2d 81, 84 (N.D. 1996); Knight v.

Jewett, 834 P.2d 696, 705-06 (Cal. 1992); Clover v. Snowbird

Ski Resort, 808 P.2d 1037, 1047 (Utah 1991); Wright v. Mt.

Mansfield Life, Inc., 96 F. Supp. 786, 791-92 (D. Vt. 1951).

Here, the risk under consideration is not a variation in terrain

but the lack of a warning sign at a hazardous variation in terrain. Given the Service’s comprehensive safety program

designed to standardize hazard notification on trails, the negligent failure to post a warning sign is not an integral part of

the sport of snowmobiling. The risk from such a failure could

be eliminated by the exercise of ordinary care. We conclude

that the snowmobile statute’s “inherent risk” provision did not

2882 OBERSON v. USDA
shield the Forest Service from liability for failure to provide

a warning of a known hazard on the Big Sky Trail. 

b. The standard of care 

To determine whether the government breached its duty to

Musselman, the district court analyzed the Forest Service’s

conduct under the ordinary care standard. The district court

arrived at this standard of care only after rejecting two alternative standards prior to trial. To the extent relevant to the

questions certified to the Montana Supreme Court, we recite

the grounds upon which the district court based its pretrial rulings. 

[8] First, the district court barred affirmative defenses

based upon the 1996 snowmobile statute’s gross negligence

standard, MONT. CODE ANN. § 23-2-653, holding that standard

of care to violate the Montana equal protection clause, MONT.

CONST. art. II, § 4. In so doing, the district court relied on

Brewer, in which the Montana Supreme Court held unconstitutional a statute eliminating legal recourse against ski area

operators for skiers suffering injury by virtue of their participation in the sport of skiing “regardless of the cause [of

injury] and regardless of the presence of negligence or intentional conduct on the part of the ski area operators.” 762 P.2d

at 230. According to the district court, the “special rights” created by the 1996 snowmobile statutes gross negligence standard were the same as those created by the statute considered

in Brewer— which removed all liability—and similarly were

not rationally related to the statutes purpose. Here, the district

court based its analogous treatment of the ski area operator

and snowmobile statutes upon its unpublished order in Riska

v. USDA, CV-96-63-BU-DWM (D. Mont. Oct. 14, 1997)

(holding 1996 snowmobile statute’s gross negligence standard

unconstitutional under Brewer). We have found no Montana

court decisions resolving the constitutionality of the 1996

snowmobile statute’s gross negligence standard or Brewer’s

OBERSON v. USDA 2883
applicability to gross negligence standards of care in other

statutes. 

[9] Second, the district court barred affirmative defenses

based upon the recreational use statute’s willful or wanton

misconduct standard, MONT. CODE ANN. § 70-16-302(1).

According to the district court, the parties agreed that the

Montana legislature “carved snowmobiles out of the general

recreational use statute by enacting the specific snowmobile

liability statutes.” The government argued the recreational use

statute’s willful or wanton misconduct standard still should

apply in place of the snowmobile statute’s rejected gross negligence standard. The district court, however, held the recreational use statute to be preempted by the more specific

snowmobile liability statute in this instance. Having found the

recreational use statute’s standard of care inapplicable, the

district court instructed the parties to proceed under the catchall ordinary care standard, MONT. CODE ANN. § 27-1-701, citing Brewer, 762 P.2d at 230, and Mead v. M.S.B., Inc., 872

P.2d 782, 786-87 (Mont. 1994). We have found no Montana

court decisions addressing whether the snowmobile liability

statute’s standard of care preempts the recreational use statute’s standard in this context. 

[10] The Montana Supreme Court’s decision regarding the

appropriate standard of care will be dispositive of this appeal.

If the Court endorses the application of the ordinary care standard, we find no reason to overturn the district court’s decision. However, if the Court holds the gross negligence or

willful or wanton misconduct standard applicable, we must

remand the case to the district court for a new trial under the

appropriate standard of care. 

2. Causation

The government contends first that there was no causal

relationship between the absence of a warning and Musselman’s injury. We review a district court’s findings of both

2884 OBERSON v. USDA
cause-in-fact and proximate cause for clear error. Husain v.

Olympic Airways, 316 F.3d 829, 835 (9th Cir. 2002) (reviewing mixed questions of law and fact regarding proximate

cause); United States v. Hackett, 311 F.3d 989, 991 (9th Cir.

2002) (reviewing factual findings regarding causation). 

[11] “[A] party’s conduct is a cause-in-fact of an event if

the event would not have occurred but for that conduct.” Gentry, 962 P.2d at 1209 (internal quotation marks and citation

omitted). The record established that when approaching the

hill at only 35 mph (below the speed limit), a snowmobile

would leave the ground and sail over the crest of the hill with

the operator losing control and unable to see objects at the

foot of the hill, as occurred in the earlier collision of a snowmobile with the snow groomer at the same location. As the

district court found, “[p]lacing a sign on the approach to this

hill would have changed the riders’ expectancies and

informed them that the approaching hill was far steeper than

the usual gentle grade.” Oberson v. United States, 311 F.

Supp. 2d 917, 959 (D. Mont. 2004). Musselman, having

landed off the trail, saw Johnson on the trail and reentered it,

as the court found, to assist or warn the other snowmobilers

of the danger. He was hit when Kalahar and Leinberger,

unwarned, sped over the hill’s crest and lost control of their

snowmobiles as a result of the unexpected steep grade. The

court found that “but for the hill and the associated problems

found in the facts, the accident would not likely have

occurred.” Cause-in-fact, therefore, was established on the

record which showed that the Service’s conduct, “in a natural

and continuous sequence . . . helped produce [Musselman’s]

injury and [the injury] would not have occurred without it.”

Busta, 916 P.2d at 139. 

The Forest Service’s principal contention is that Kalahar

and Leinberger’s speed and intoxication combined with Musselman’s carelessness in entering the trail were independent

intervening causes. Even if its failure to post a warning sign

were found to be a cause-in-fact of Musselman’s injuries, the

OBERSON v. USDA 2885
Forest Service argues, the riders’ acts were unforeseeable

intervening causes, sufficient to prevent a finding that the Forest Service’s failure to warn was a proximate cause of the

accident. 

Where, as here, the existence of independent intervening

acts is alleged, causation requires proof of both cause-in-fact

and proximate cause. Gentry, 962 P.2d at 1209. “When two

or more causes concur to bring about an event, then cause-infact is established by the ‘substantial factor’ test.” Sletteland

v. Roberts, 16 P.3d 1062, 1067 (Mont. 2000) (citation omitted). Under that test, a party held to have contributed to an

event is not “absolved from that responsibility upon the

ground that the identical harm would have occurred without

[its involvement].” Rudeck v. Wright, 709 P.2d 621, 628

(Mont. 1985). As the foregoing discussion shows, the Service’s maintaining the hazardous and unwarned condition of

the hill contributed to the event in which Musselman was

injured. 

[12] Proximate cause is established when a party could reasonably foresee that its conduct would result in injury. Busta,

916 P.2d at 135. An independent intervening act will not bar

liability if it is “one that the defendant might reasonably foresee as probable or one that the defendant might reasonably

anticipate under the circumstances.” Estate of Strever v.

Cline, 924 P.2d 666, 672 (Mont. 1996). However, “[t]he particular resulting injury need not have been foreseeable.”

Hinkle v. Shepherd Sch. Dist. # 37, 93 P.3d 1239, 1245

(Mont. 2004). 

[13] That serious accidents involving snowmobiles could

occur at the site of the hill was foreseeable. The district court

found that the potential severity of the earlier snow groomer

accident, even though no one was injured, placed the Forest

Service on notice that serious injury could result from its failure to post a warning. That riders would operate snowmobiles

negligently was foreseen by the Service. Its awareness of rid2886 OBERSON v. USDA
ers’ high speeds was a motivation for implementing a trail

warranting process. And its awareness of intoxicated persons

operating snowmobiles is reflected in the Code of Federal

Regulations’ express prohibition of operation of a snowmobile while intoxicated in a National Park or Forest. 36 C.F.R.

§§ 2.18, 4.23 (1996). Thus, Kalahar’s and Leinberger’s negligence was foreseeable. 

[14] The Montana Supreme Court has long recognized the

rescue doctrine.6 Under that doctrine, “one who, observing

another in peril, voluntarily exposes himself to the same danger in order to protect him . . . may recover for any injury sustained in effecting the rescue against the person through

whose negligence the perilous condition has been brought

about.” Bracey v. Nw. Improvement Co., 109 P. 706, 707

(Mont. 1910); see also Brown v. Columbia Amusement Co.,

6 P.2d 874, 878 (Mont. 1931). Although the cases speak

broadly in terms of liability, they recognize that liability is

intertwined with causation in the application of the doctrine.

Thus, in Kiamas v. Mon-Kota, Inc., 639 P.2d 1155, 1159

(Mont. 1982), the court held that causation had not been

established where action was no longer required to avert a

threatened harm. In its discussion of “Scope of Liability

(Proximate Cause),” the Restatement of Torts (Third) (Proposed Final Draft) states, with respect to rescuers, “The aspect

relevant to scope of liability provides that an actor whose tortious conduct puts the actor or another at risk, is subject to liability to a third person who is injured while attempting to

come to the aid of the actor or the other imperiled person.”

§ 32 cmt. b (2005). Musselman’s entry onto the trail, the district court found, was a response to the peril created by the

Service to warn or give aid to other snowmobilers. As such,

it was a foreseeable consequence of the Service’s negligence.

6

“Danger invites rescue. The cry of distress is the summons to relief.

The law does not ignore these reactions of the mind in tracing conduct to

its consequences. It recognizes them as normal. It places their effects

within the range of the natural and probable.” Wagner v. Int’l Ry. Co., 133

N.E. 437, 437 (N.Y. 1921) (Cardozo, J.). 

OBERSON v. USDA 2887
V. NOTICE

The clerk of this court shall forward a copy of this order,

under official seal, to the Montana Supreme Court, along with

copies of all briefs and excerpts of record that have been filed

with this court. The parties shall notify the clerk of this court

within fourteen (14) days of any decision by the Montana

Supreme Court to accept or to decline certification. If the

Montana Supreme Court accepts certification, the parties shall

then notify the clerk of this court within fourteen (14) days of

the issuance of the Court’s opinion. Submission of the questions presented in this appeal will be vacated by separate

order pending the Montana Supreme Court’s response to this

request.

VI. COUNSEL LIST

The following is a list of counsel appearing this matter:

Counsel for Plaintiffs/Appellants Lori Oberson, Legal Guardian for Brian Musselman, Kimberlee Musselman, individually

and as Natural Mother of Devon Musselman, a minor, 

Tom L. Lewis 

Lewis Slovak & Kovacich 

P.O. Box 2325 

Great Falls, MT 59403

and 

Andrew D. Huppert 

Petit Hock & Huppert 

P.O. Box 8718 

111 N. Higgins Avenue 

Missoula, MT 59807 

Counsel for Defendant/Third-Party Plaintiff/ Appellee United

States Department of Agriculture, Forest Service 

Bernard F. Hubley 

USHE - Office of the U.S. Attorney 

2888 OBERSON v. USDA
901 Front Street 

Helena, MT 59626

and 

H. Thomas Byron, III 

U.S. Department of Justice 

Civil Division/Appellate Staff 

950 Pennsylvania Avenue, NW 

Washington, DC 20530-0001 

Counsel for Defendant/Third-Party Plaintiff State of Montana,

by and through the Department of Fish, Wildlife and Parks 

Lucy T. France 

Garlington Lohn & Robinson, PLLP 

P.O. Box 7909 

199 West Pine 

Missoula, MT 59807-7909 

Counsel for Defendant/Third-Party Plaintiff West Yellowstone Chamber of Commerce 

Gig A. Tollefsen 

Berg Lilly & Tollefsen 

1 West Main Street 

Bozeman, MT 59715 

Counsel for Third-Party Defendant Jamie Louis Leinberger 

Jamie Louis Leinberger 

303 South Dean 

Bay City, MI 48706 

Counsel for Third Party Defendant Patrick B. Kalahar 

Marshal L. Mickelson 

Corette Pohlman Allen Black & Carlson 

Mayer Building 

129 West Park Street 

P.O. Box 509 

Butte, MT 59703 

Third-Party Defendant Tim A. Johnson 

No Appearance 

OBERSON v. USDA 2889
Respectfully submitted,

Ronald M. Gould, Marsha S. Berzon

Circuit Judges and

William W Schwarzer, Senior United

States District Judge for the Northern

District of California, sitting by

designation

Ronald M. Gould, Circuit Judge,

Presiding

2890 OBERSON v. USDA