OPINION
{ 1 Following the trial court's denial of his motion to suppress evidence, Defendant Robert Nicholas Despain pleaded guilty to one count of driving under the influence of alcohol or drugs, see Utah Code Ann. § 41-6-44 (2004) (current version at Utah Code Ann. § 41-6a-502 (2005)), and one count of possession of a controlled substance, see Utah Code Ann. § 58-87-8(1)(a)(@iii) (2002). Defеndant now appeals, claiming that the trial court erred (1) by finding that the police officers had probable cause to arrest him for driving under the influence and (2) by admitting evidence produced in a warrantless search of Defendant's vehicle. We conclude that the officers had probable cause to arrest Defendant fоr driving under the influence of drugs where the arresting officer observed Defendant's slurred speech, received witness reports of Defendant's erratically dangerous driving just prior to the collision, and noted that Defendant had collided with a trailer parked on the side of the road. We also conclude that the officers' search of Defendant's vehicle was justified under the automobile exception to the Fourth Amendment's warrant requirement and that the evidence obtained therein was admissible. According ly, we affirm.
*215 BACKGROUND 1
12 On the evening of May 6, 2004, Defendant swerved in and out of his lane of traffic and crashed his car into a trailer parked on the side of the road. Deputy Spоtten arrived at the seene and approached Defendant, who was leaning against the trailer. Defendant denied having consumed alcohol or drugs, and Deputy Spotten did not detect the odor of alcohol or marijuana emanating from Defendant. Deputy Spotten observed, however, that Defendant's speech was slurred.
T3 At the scene, three eyewitnesses spoke with Deputy Spotten and described Defendant's driving pattern just prior to the collision. They told Deputy Spotten that Defendant had been driving in an erratic and dangerous manner. Specifically, they indicated that Defendant ran another car off the road, caused the car to hit a reflector post, swerved in front of a semi-truck to make a left-hand turn, nearly hit the semi-truck, and then swerved several times across the entire road before crashing into the back of the parked trailer. Another officer, Sergeant Mazuran, arrived at the scene and observed Defendant's behavior as "panicked."
{4 Based on Defendant's erratically dangerous driving pattern, his collision with a stationary trailer, and his slurred speech and panicked demeanor, the officers determined that they had probable cause to arrest Defendant for driving under the influence of drugs. Because Salt Lake County medical personnel were preparing to transport Defendant to the hospital for treatment of his injuries, Deputy Spotten chose not to administer a field sobriety test and did not inform Defendant at the seene of the collision of his intent to arrest him. Instead, Deputy Spot-ten followed the ambulance to the hospital and arrested Defendant there, after Defendant had recеived medical treatment.
[5 Prior to Defendant's transport to the hospital, Deputy Spotten received reports from Salt Lake County medical personnel that Defendant was acting paranoid. They indicated to Deputy Spotten that Defendant repeatedly expressed concern about the contents of his cаr and that Defendant had locked his car to keep people out. Defendant's unusually great concern about the contents of his vehicle increased Deputy Spot-ten's suspicions because this concern was inconsistent with the deputy's prior law en-foreement experience with victims of car accidents. Dеputy Spotten retrieved the keys from Defendant and unlocked the door of the car. After the car was unlocked, and before any search was performed, two individuals arrived and claimed to be related to Defendant. The individuals went to the car and one attempted to retrieve a backpack from the back seat. Upon Deputy Spotten's instruction to stop, the individual returned the backpack to the car.
1 6 At that point, Sergeant Mazuran began searching Defendant's car. As he found particular items in the vehicle, Sergeant Mazu-ran took the items to Deputy Spotten and told him where the items had been found. Sergeant Mazuran's search of thе vehicle produced a bag of marijuana from the driver's side door compartment, a backpack, and a box. A search of the backpack revealed marijuana that had been prepared for distribution, and a search of the box revealed a quantity of methamphetamine.
17 The trial court concluded thаt Deputy Spotten had probable cause to arrest Defendant for driving under the influence, although the actual arrest did not occur until after the search of Defendant's vehicle. The trial court ruled that although the prosecution failed to present sufficient information to determine whether the search was an inventory search pursuant to departmental policy, the contraband in the vehicle would have been inevitably discovered after the vehicle had been impounded. The trial court therefore determined that the evidence produced in the search of Defendant's vehicle was admissible pursuant to the inevitable discovery rule. On appeal, the State concedes that the inevitable discovery rule is not applicable *216 because there is no evidence that the vehicle would have been searched a second time after impound. The State argues, however, that the decision to admit the evidence should be affirmed because the warrantless search of Defendant's vehicle was justified under the automobile exception to the Fourth Amendment.
ISSUES AND STANDARD OF REVIEW
T8 Defendant challenges the trial court's finding of probable cause to arrest him for driving under the influence of drugs and the admissibility of evidence found during the warrantless search of his vehicle. "In search and seizure cases, we review the district court's factual findings 'under a clearly erroneous standard."" State v. Ranquist,
ANALYSIS
I. Probable Cause to Arrest
19 Defendant claims that Deputy Spotten lacked probable cause to arrest him for driving under the influence because Deputy Spotten relied only on reports of Defendant's erratic driving, did not conduct a field sobriety test, and could not detect the odor of alcohol or marijuana on Defendant's person.
2
"[Tlo justify a warrantless arrest 'an officer must have probable cause ... to believe that the suspect has committed or is committing an offense."" State v. Hechtle,
{10 Under the totality of the cireum-stances, Deputy Spotten had sufficient probable cause to bеlieve that Defendant had been driving under the influence of drugs. A person is guilty of driving under the influence if the person "operate[s] or [is] in actual physical control of a vehicle ... [and] the person ... is under the influence of alcohol, any drug, or the combined influence of alcohol and any drug to a degree that renders the person incapable of safely operating a vehicle." Utah Code Ann. § 41-6-44(@)(a)@) (2004) (current version at Utah Code Ann. § 41-6a-502(1)(b) (2005)). Several facts provided Deputy Spotten with probable cause to believe that Defendant had committed this crime: Defendant had been driving in an erratic and dangerous manner; Defendant had slurred speech; and Defendant ended *217 his dangerous driving in an unusual accident-a single-car collision with a trailer parked on the side of the road. Therefore, Deputy Spotten was justified in making a warrant-less arrest of Defendant.
II. Admissibility of the Evidence
111 Defendant claims that the trial court erred by concluding that the inevitable discovery doctrine justified the admission into evidence of items produced during the officers' warrantless search of his vehicle. The State concedes this point but argues that we may affirm the admission of the evidence under the automobile exception to the Fourth Amendment's warrant requirement. "[Aln appellate court may affirm the judgment appealed from 'if it is sustainable on any legal ground or theory apparent on the record."" Bailey v. Bayles,
112 Although Defendant mentioned both the Utah and United States Constitutions in his opening brief, he did not conduct a separate analysis of the protections afforded by each. In fact, when responding to the State's arguments regarding the automobile exception, the only constitutional provision Defendant explicitly referenced was the Fourth Amendment of the United States Constitution. Utah appellate courts "have repeatedly refrained from engаging in state constitutional law analysis unless 'an argument for different analyses under the state and federal constitutions is briefed." State v. Worwood,
$18 Under the Fourth Amendment of the United States Constitution, law enforcement officers must obtain a warrant before conducting a search. See U.S. Const. amend. IV. However, the automobile exception to the warrant requirement provides that " 'ilf a car is readily mоbile and probable cause exists to believe it contains contraband, the Fourth Amendment ... permits police to search the vehicle without more.'" Maryland v. Dyson,
114 Admittedly, federal law has fluctuated in the past with respect to the exact conditions that justify a warrantless search under the automobile exception to the Fourth Amendment. Under our earlier reading of the underlying federal case law, Utah courts concluded that a warrantless search of a vehicle was not proper unless there was both probable cause to believe that the vehicle contained contraband and exigent circumstances indicating a likelihood that the evidence may be destroyed or lost if not immediately seized. See, e.g., State v. Christensen,
*218
precedent, the 'automobile exception' has no separate exigenсy requirement." - Dyson,
1 15 Similarly, the Supreme Court has also clarified that, "although ready mobility alone was perhaps the original justification for the vehicle exception, our later cases have made clear that ready mobility is not the only basis for the exception." California v. Carney,
116 The officers' search of Defendant's vehicle wаs justified under the automobile exception to the Fourth Amendment's warrant requirement because the officers had probable cause to believe that Defendant's vehicle contained contraband. Eyewitnesses gave Deputy Spotten accounts of Defendant's erratic driving pattern just prior to the accident. Paramedics also informed Deputy Spotten that Defendant was "acting paranoid" and that he was "continually worried about his car." Defendant locked his car to keep people out. The individuals summoned by Defendant to the accident seene attempted to enter the car and remove items from it prior to its impound. In Dеputy Spotten's experience, this sort of behavior was inconsistent with the behavior of other accident victims, who are primarily concerned about their injuries and what is going to happen to them, only later becoming concerned about the car and items therein. Because these facts gave the officers probable cause to believe that the vehicle contained contraband, the warrantless search was valid and the evidence produced therefrom was properly admitted.
CONCLUSION
1 17 We conclude that Deputy Spotten had probable cause to arrest Defendant for driving under the influence of drugs where he observed Defendant's slurred speech, received witness reports of Defendant's dangerous and erratic driving just prior to the collision, and observed that Defendant had collided with a trailer parked on the side of the road. We also conclude that the officers' search of Defendant's vehicle was justified under the automobile exceрtion to the Fourth Amendment's warrant requirement because the officers had probable cause to believe that Defendant's vehicle contained contraband. Thus, the evidence obtained through that search was admissible.
{[ 18 We therefore affirm.
119 I1 CONCUR: PAMELA T. GREENWOOD, Associate Presiding Judge.
20 I CONCUR, EXCEPT THAT AS TO SECTION II, I CONCUR ONLY IN THE RESULT: JUDITH M. BILLINGS, Judge.
Notes
. - '"We recite the facts in the light most favorable to the trial court's findings from the suppression hearing." State v. Giron,
. Defendant argues that the absence of certain physical signs, such as bloodshot eyes and noticeable odors on the breath or person, prevents an officer from having probable cause to arrest a person for driving under the influence. The absеnce of such signs, however, does not foreclose a determination of probable cause. Other objective signs and factors, particularly when viewed under the totality of the circumstances, may legitimately give rise to probable cause to believe that a person has driven under the influence of alcohol оr drugs. Furthermore, some illegal drugs do not produce physical side effects, such as bloodshot eyes, or leave strong odors after use. Thus, the absence of these particular physical signs may, in conjunction with other evidence of impairment, indicate nothing more than that a given person is under the influence of drugs other than alcohol or marijuana.
