delivered the opinion of the Court.
Donald Hulett, d/b/a East Valley Trucking, and Steven Luksha appeal the Jefferson County District Court order granting Charles Shannon a new trial. We reverse.
On September 22, 1979, Shannon was driving his 1966 Chevrolet northbound on 1-15 at about 35 m.p.h. Luksha was driving a 1972 Kenworth truck with a pup-trailer, owned by his employer Hulett, southbound on 1-15 approximately 40 to 45 m.p.h. Both drivers were on a two-lane portion of 1-15 just south of Boulder, which in many places was in poor condition.
The record indicates that because of the rough shoulder, Luksha was very close to the centerline. Just after he entered the two-lane highway, five oncoming cars passed by him, and he checked their progress in his rearview mirror. *347When he looked forward he saw Shannon cutting through an approaching curve one or two feet in his lane of travel. Luksha testified that it appeared a head-on collision was imminent, so he swerved his truck to the right. This sudden action and the rough road caused the truck to lean badly and Luksha almost lost control. It also caused the pup-trailer to swing out into Shannon’s lane of travel. The left side of the trailer collided with the front and top of Shannon’s vehicle. Shannon suffered serious injury.
Shannon brought an action in Jefferson County District Court against appellants seeking damages arising from the accident. By special verdict the jury found appellants not “guilty of negligence which was the proximate cause of the claimed damage.”
Thereafter, Shannon moved the court to set aside the jury verdict and to grant a new trial. The District Court granted a new trial without supporting memorandum. An appeal was brought to this Court which filed its opinion on January 19, 1983. This Court dismissed the appeal without prejudice and remanded the case to the District Court for reconsideration and entry of an order stating the grounds for granting a new trial in compliance with Rule 59(f), M.R.Civ.P. Shannon v. Hulett (1983), 202 Mont. 205, 656 P.2d 825, 40 St.Rep. 35. The remittitur was filed in District Court on February 1, 1983. On that same day, District Judges Frank Blair (retired) and Frank Davis complied with this Court’s order by filing memoranda in support of the order granting Shannon’s motion for a new trial in the District Court for Jefferson County. Luksha and Hulett appeal the order granting a new trial. They raise two issues for our consideration:
1. Was the District Court’s order and memorandum in support of order procedurally proper and indicative of actual consideration given to its decision?
2. Did the District Court abuse its discretion by granting a new trial?
We reverse on the ground that the District Court abused *348its discretion in setting aside the jury verdict. The first issue is thus moot, and we do not address it.
Essentially, appellants contend that a new trial may not be granted if there is substantial evidence to support the jury verdict. Here, there are sufficient facts to support the jury’s verdict that Luksha was free from negligence, and the District Court abused its discretion in setting aside the verdict.
Shannon argues that there is no conflicting evidence which can support the jury determination that Luksha was free from negligence. He was negligent as a matter of law when the trailer crossed into Shannon’s lane of travel. Shannon’s injuries were proximately caused by such negligence.
The standard for granting a new trial is well established in Montana. If there is substantial evidence supporting the verdict, a new trial may not be granted. Stenberg v. Neel (1980), Mont., 613 P.2d 1007, 37 St.Rep. 1170; Lyndes v. Scofield (1979), 180 Mont. 177, 589 P.2d 1000; Kincheloe v. Rygg (1968), 152 Mont. 187, 448 P.2d 140; Hinton v. Peterson (1946), 118 Mont. 574, 169 P.2d 333. Neither may a District Court grant a new trial simply because it believed one line of testimony different from that which the jury believed. Yerkich v. Opsta (1978), 176 Mont. 272, 577 P.2d 857; In re Estate of Hardy (1958), 133 Mont. 536, 326 P.2d 692.
When a District Court denies a motion for a new trial, we are less inclined to disturb that order because the lower court has indicated faith in the jury verdict. However, when a District Court is presented with evidence in favor of the verdict but proceeds to grant a new trial, it is our duty to test the evidence against the verdict. Campeau v. Lewis (1965), 144 Mont. 543, 549, 398 P.2d 960, 963.
We find there is sufficient evidence to support the jury’s verdict. The evidence is undisputed that Shannon, while driving northbound on 1-15, cut through a curve in the opposing lane. Luksha, approaching Shannon, responded by swerving to the right to avoid a head-on colli*349sion. There was no evidence indicating that Luksha was driving unsafely prior to observing Shannon or that he was negligent in any other way.
By special verdict the jury found that neither Luksha nor his employer were guilty of any negligence which proximately caused the claimed damage.
Court’s Instruction Nos. 3 and 4 state:
“Every person is responsible for injury to the person or property of another, caused by want of ordinary care or skill.
“When used in these instructions, negligence means want of ordinary care or skill. Such want of ordinary care or skill exists when there is a failure to do that which a reasonable and prudent person would ordinarily have done under the circumstances of the situation, or doing what such person under the existing circumstances would not have done.” Instruction No. 3.
“You are instructed that a violation of law is of no consequence unless it was a proximate cause of (or contributed as a proximate cause to) an injury found by you to have been suffered by the Plaintiff.” Instruction No. 4.
Under the facts of the case and within the parameters of the above instructions the jury could have, first of all, found Luksha committed no negligence. There was no evidence indicating he was negligent prior to taking evasive action. Further, Luksha acted as any reasonable and prudent person would when facing an imminent head-on collision — he moved out of the way.
Secondly, the fact that Shannon was driving into the oncoming lane when approaching Luksha further supports a finding that such action was the proximate cause of Shannon’s injuries.
We vacate the order granting a new trial. We reinstate the jury verdict and the judgment entered thereon.
MR. JUSTICES HARRISON and GULBRANDSON concur.