This is the second appeal relating to the judgments of conviction of Albert Bell. Terry Sims and Albert Bell gave statements to law enforcement officers confessing to the murders of Julian Russell and Mary Lou Jones at Cloud’s Grocery Store in Casscoe, Arkansas County. At the ensuing trial of Albert Bell, he was convicted of both murders and sentenced to two consecutive life sentences. We remanded for the limited purpose of a new suppression hearing because the prosecutor failed to make available State Police Sergeant Gary Allen, who allegedly played “bad cop” to Officer John McCord’s “good cop” in the *425police interrogation of Bell. See Bell v. State, 324 Ark. 258, 920 S.W.2d 821 (1996). We said in this decision that a new trial would only be warranted in the event that Bell’s statement was suppressed by the trial court on remand. Bell’s remaining points on appeal were rejected by this court.
Following the remand, Bell filed an amendment to his motion to suppress. In the motion, Bell complained that he was not allowed to consult with counsel despite requesting to speak with an attorney and, further, was not allowed to consult his parents. Bell also complained “[t]hat each of the statements was taken in violation of the Arkansas Rules of Criminal Procedure, specifically Rules 2.2 through 3.5.” At the suppression hearing on remand, State Police Investigator John McCord testified that he first spoke with Bell, who was age 16, on January 5, 1993. Officer McCord testified that on that day, he and State Police Officer Lloyd Franklin waited at the Stuttgart Fligh School for Bell to be dismissed from class. He testified that he had told Bell in the principal’s office that he did not have to go to the Arkansas County Sheriffs Department with them. When school was out, the police officers called Bell and Sims over to an unmarked police car and placed them in the back seat. They then drove the two young men to the sheriff s department for questioning. After leaving the high school, Officer McCord did not tell Bell again that he was free to leave.
Bell’s interview at the sheriffs department took about 30 minutes and his mother was with him during the interview. Officer McCord testified that Bell was not a suspect at this time and was free to leave. He admitted that Sims left the sheriffs department during this time and was chased by police officers. It was later revealed that Sims returned on his own. Officer McCord testified that he did not read Bell his Miranda warnings at this time because Bell was not a suspect. Rather, he questioned Bell because Bell was a friend of Sims and because Bell had been seen near the store about the time of the murders. Bell denied being with Sims on the day of the murders.
Deputy Sheriff David Box testified that he was instructed to locate Bell on January 8, 1993, and bring him to the sheriffs *426department for questioning. He found Sims and Bell at Bell’s grandmother’s house, but they were not placed under arrest or handcuffed. Deputy Box testified that if the two young men had refused to go with him, he would have radioed the sheriff for instructions. He admitted that he did not tell Sims and Bell that they did not have to accompany him.
Officer McCord testified that he interviewed Bell a second time on January 8, 1993, but this time Bell was considered a suspect. He testified that the investigation began to focus on Sims on January 5, 1993, because Sims had given inconsistent times when he returned a videotape to Cloud’s Grocery Store. The state police officer also stated that Sims’s neighbor was missing a .22 revolver, which was the caliber of the gun used in the Casscoe murders. He added that Bell acknowledged he understood his Miranda rights on January 8, 1993; that he agreed to speak with him; and that he initialed the separate Miranda warnings and signed the waiver of rights form. In the first statement taken from Bell on January 8, 1993, Bell repeatedly denied that he was with Sims on the night of the murders. However, Officer McCord knew that Eddrick Bell, Albert Bell’s brother, on the previous day had placed Bell with Sims on the night in question. Eddrick Bell told the police officers that Sims had picked up Bell at about 7:00 p.m. that evening. When confronted with this statement, Bell admitted that he had been with Sims and that he accompanied Sims to Cloud’s Grocery Store. He further told the interrogating officers that he sat in the car and saw Jeanette Gillmore shoot Julian Russell in the grocery store and that Sims ran out of the store while the shooting was in progress.
Officer McCord related at the hearing that Bell never asked to stop the questioning or to terminate the interview on January 8, 1993, and that he never asked for a lawyer. He estimated that he talked with Bell for an hour or less. After the police officer completed his interview, Bell was turned over to State Police Investigator John Howell for a polygraph examination.
Officer John Howell explained at the suppression hearing that Bell agreed to take the polygraph exam. He testified that he inquired about Bell’s statement that a Jeanette Gillmore had done *427the shooting, but Officer Howell stated that the polygraph test showed that Bell was being deceptive with his answers. Bell told Officer Howell that he would tell the truth if allowed to speak with Sims first. He was told that he could talk to Sims only after he told the truth. Bell then told Officer Howell that Sims shot the victims: “Terry just lost it and started shooting.” Bell wanted to make a plea at that time, and Officer Howell informed him that only the prosecuting attorney had the authority to agree to a plea. Bell was allowed to speak with Sims, and he told Sims that he was going to tell the truth “regardless of what Terry had to say.” Sims then agreed to tell the truth, and he confessed to shooting the two victims.
Officer John McCord had first testified that he did not believe he had probable cause to arrest Bell on January 8, 1993. When he retook the stand at a later date, he testified that it was “borderline” but he thought there was probable cause to arrest on January 8, 1993.
State police sergeant Gary Allen testified that he “sat in” on the January 8, 1993 interrogation. He denied that he conducted the interview or threatened or coerced Bell to make a statement. He did admit to telling Bell that he was lying.
Bell took the stand at the suppression hearing, as did his parents, who testified that they were excluded from the January 8, 1993 interview. Bell denied that he knew what a Miranda right was. He admitted that he had a juvenile offender history but denied that he had ever been read his Miranda rights previously. He stated that he had since learned of his rights in prison. Bell admitted that Officer McCord read him his rights on January 8, 1993, but he stated that Officer McCord did not explain what those rights meant. Bell admitted that he initialed the paragraphs on the waiver form and signed it because he was told to do so. He further stated that he requested an attorney. He did not think he could leave on January 8 because the police officers had chased Sims when he left the sheriff’s department on January 5.
On cross-examination, Bell admitted that he was told that he had the right to remain silent, but he felt compelled to answer the questions that were being asked to him. He further testified that *428he had heard Miranda warnings read in television programs but revealed that he did not understand them. Bell admitted that he did not ask for an explanation of his rights. He also indicated that at least some of his rights had been explained to him as a juvenile. Bell added that while he understood the words of the warnings, he did not understand what they meant.
The trial court entered its order and concluded that Rule 2.3 was not complied with when Bell was picked up from high school for questioning on January 5, 1993. Moreover, he was not advised of his Miranda rights on that date. The trial court observed that Rule 2.3 was also not complied with when Bell was picked up for questioning on January 8, 1993. Nor, according to the trial court, did police officers have probable cause to arrest him at that time. The court then stated:
The record does not reflect any effort taken by the state to comply with Rule 2.3 nor any efforts by the state to determine whether the waiver executed by the defendant was made with a full awareness of both the nature of the rights being abandoned and the consequences of the decision to abandon them.
However, the court agreed that Bell had acknowledged that he understood his rights when they were read to him.
The court suppressed the statements made by Bell on both January 5 and January 8, 1993, and the State has appealed that order.
I. Rule 2.3
The State first disagrees that a violation of Ark. R. Crim. P. 2.3 transpired. Rule 2.3 states:
If a law enforcement officer acting pursuant to this rule requests any person to come to or remain at a police station, prosecuting attorney’s office or other similar place, he shall take such steps as are reasonable to make clear that there is no legal obligation to comply with such a request.
Ark. R. Crim. P. 2.3 (emphasis added). The State malees three arguments under this point on appeal: (1) the consideration of Rule 2.3 was barred by the law-of-the-case doctrine; (2) the trial *429court erred in concluding that Rule 2.3 was violated on January 5, 1993; and (3) any violation of Rule 2.3 on January 8, 1993, was immaterial because there was probable cause to arrest Bell at that time.
Law of the case.
The State contends that Bell was barred on remand from arguing that there was a Rule 2.3 violation because he had failed to argue that point in his first appeal. As a result, the State contends, the asserted error was barred by the doctrine of law of the case. Bell answers that the State’s argument is not preserved for appeal because it was not raised in the trial court. While the State contends that the argument is jurisdictional, Bell urges that it is merely an affirmative defense.
Bell is correct that the law-of-the-case defense cannot be raised for the first time on appeal. It is undisputed that the State failed to make this argument to the trial court. Moreover, this court has previously recognized that law of the case is an affirmative defense like estoppel or res judicata. See Earney v. Brantley, 309 Ark. 190, 828 S.W.2d 832 (1992). The defense is not preserved for our review.
Violation of Rule 2.3 on January 5, 1993.
The State next contends that the trial court overlooked the uncontroverted testimony from Officer McCord that he told Bell at the Stuttgart High School on January 5, 1993, that he did not have to accompany him to the sheriff’s department. Under the bright-line rule, according to the State, this was all that was required. Bell counters with the assertion that the evidence must be viewed in his favor, and that the trial court found no such Rule 2.3 admonition was given.
We decline to address the merits of this issue because it appears patently clear that Bell did not incriminate himself with his statement on January 5, 1993. Indeed, on that day he was not a suspect, and he told police officers that he was not at Cloud’s Grocery Store or with Terry Sims on the night of the murders. He was subsequently found to be lying, but no incriminating evi*430dence was obtained from Bell as a result of his interview on that date. We conclude that any error associated with the January 5, 1993 interview was harmless beyond a reasonable doubt. See Martin v. State, 328 Ark. 420, 944 S.W.2d 512 (1997).
Violation of Rule 2.3 on January 8, 1993.
The State next contends that there could be no violation of Rule 2.3 on January 8, 1993, because Rule 2.3 had been complied with on January 5, 1993 and there was probable cause to arrest Bell on January 8th. Both the criminal rules and our caselaw recognize that if a police officer has probable cause to arrest, failure to give a Rule 2.3 warning is irrelevant. See Ark. R. Crim. P. 2.1; see also Addison v. State, 298 Ark. 1, 765 S.W.2d 566 (1989). Probable cause exists when there is reasonably trustworthy information within law enforcement’s knowledge that would lead a person of reasonable caution to believe that a felony was committed by the person detained. Hart v. State, 312 Ark. 600, 852 S.W.2d 312 (1993); Addison v. State, supra; Burks v. State, 293 Ark. 374, 738 S.W.2d 399 (1987).
The essential facts that were available to law enforcement on January 8, 1993, were that Terry Sims had lied to them about the time he returned the movie to Cloud’s Grocery Store on the day of the murders; that Sims was at the grocery store when the murders occurred; that a .22 caliber pistol was missing from the home of a friend of Sims, and that was the caliber of pistol used in the killings; that Bell told the police officers he was not with Sims after school on the day of the murders but that Bell’s brother contradicted that story; that Bell’s brother told law enforcement officers that just prior to the murders Sims came by to pick up Bell and that the two young men had earlier discussed returning a videotape and getting a soda; and that Bell returned a short time later with a soda pop.
This court has held that the test for determining probable cause rests on the collective information of the police officers. See Tillman v. State, 271 Ark. 552, 609 S.W.2d 340 (1980). We further are of the opinion that the fact that Officer McCord was contradictory about whether he had probable cause *431to arrest is not determinative of the issue. We conclude that this evidence was sufficient to lead a person of reasonable caution to believe that Sims had committed the killings while Bell was present. Even though “mere presence” does not make one an accomplice [see Ark. Code Ann. § 5-2-403 (Repl. 1993)], these facts are enough to constitute probable cause to arrest. The trial court was clearly erroneous in suppressing the January 8, 1993 statement due to the failure to give a Rule 2.3 warning and in finding that probable cause did not exist.
We further take this opportunity to state that in the future we will not interpret Ark. R. Crim. P. 2.3 to require a verbal warning of freedom to leave as a bright-fine rule for determining whether a seizure of the person has occurred under the Fourth Amendment and whether a statement to police officers must be suppressed. Rather, we will view a verbal admonition of freedom to leave as one factor to be considered in our analysis of the total circumstances surrounding compliance with Rule 2.3. In short, when interpreting Rule 2.3 in the future in deciding whether a seizure of a person has transpired, we will follow United States v. Mendenhall, 446 U.S. 544 (1980). See also Martin v. State, 328 Ark. 420, 944 S.W.2d 512 (1997)(Brown, J., concurring opinion). To the extent that our decisions in Burks v. State, supra-, Addison v. State, supra; Hart v. State, supra; Prowell v. State, 324 Ark. 335, 921 S.W.2d 585 (1996); and Martin v. State, 328 Ark. 420, 944 S.W.2d 512 (1997), state a contrary interpretation, we retreat from that interpretation.
II. Comprehension of Waiver
The State also contends that the circumstances prove that Bell had read and understood his Miranda rights on January 8, 1993, and that the trial court clearly erred in ruling otherwise. The State specifically urges that it was not required to make any special or additional effort to assess Bell’s ability to understand his rights and the consequences of a waiver. We agree.
It was undisputed that Bell had been read his Miranda rights prior to giving the statement on this date. Bell also had some familiarity with the criminal justice system due to the fact that he *432had previously been on probation as a juvenile offender. In fact, he knew that as a juvenile, he was entitled to have his parents or a lawyer present when being questioned. He was age 16 and a high school sophomore who was taking regular courses in math, science, and English, though he had also been in remedial classes since the fourth grade. He further agreed that he understood the words in his warnings but denied knowing their import.
A defendant’s waiver of Fifth and Sixth Amendment rights must be knowing and intelligent with “a full awareness of both the nature of the right being abandoned and the consequences of the decision to abandon it.” Clay v. State, 318 Ark. 122, 883 S.W.2d 822 (1994); Mauppin v. State, 309 Ark. 235, 831 S.W.2d 104 (1992). We analyze the issue of a knowing and intelligent waiver under the test of totality of the circumstances. See Humphrey v. State, 327 Ark. 753, 940 S.W.2d 860 (1997); Bradford v. State, 325 Ark. 278, 927 S.W.2d 329 (1996). Bell was 16 at the time of his confession. He was in the 10th grade and apparently on track to graduate from high school. Moreover, he had some experience with the criminal justice system, and he initialed each of his Miranda rights after reading them. He further agreed that he knew what the words meant.
Balanced against these factors is Bell’s self-serving statement that he did not realize the consequences of a waiver. He also contends that he requested counsel, which partially flies in the face of his contention that he did not understand his Miranda rights.1 While it is true that we defer to the trial court’s assessment of credibility [State v. McFadden, 327 Ark. 16, 938 S.W.2d 797 (1997)], here the trial court provides no insight as to why it found that Bell did not understand the consequences of what he was doing. Indeed, the factors clearly preponderate in favor of a knowing and intelligent waiver. The mere statement of the accused that he did not comprehend a waiver’s significance is not enough in light of his statement that he understood the words and his acknowledgment to the officers that he understood his rights. *433We hold that the trial court clearly erred in suppressing the statement of Bell on this basis.
Because we reverse the decision of the trial court, a new trial is not warranted. See Bell v. State, supra. A mandate will be issued affirming the convictions and sentences in this case.
Reversed.
Newbern, Glaze, and Imber, JJ.,. dissent.