OPINION
We granted certiorari to consider whether a stay of the proceedings to determine a defendant’s competency to stand trial recommences the six-month speedy trial rule, SCRA 1986, 5-604, after a finding of competency.
The facts relevant to this case as set out in the court of appeals’ opinion are as follows. On November 17, 1986, the petitioner, the State of New Mexico, charged defendant-respondent, Wenseslado T. Mendoza, by criminal information with possession of a controlled substance, cocaine, with intent to distribute. Mendoza posted bond and was released. On November 25, 1986, he was arraigned and entered a plea of not guilty. Although it is unclear from the record which party made the oral motion, on April 20, 1987, the trial court entered an order suspending the proceedings to determine the mental competency of respondent to stand trial. Both sides concurred in that order. On June 16, 1987, the State moved for an independent examination of respondent to determine competency. Mendoza had already been examined by an organization called Counseling Associates, Inc., but neither party had yet received a report from them. The trial court on August 19, 1987, entered an order allowing the independent examination. On November 17, 1987, the court held a hearing to determine respondent’s competency. The parties stipulated to the admission of the Counseling Associates’ report and to lifting the suspension of the proceedings. Defense counsel stated, however, that he was not waiving any time limits regarding the trial. Based on the report, the trial judge found respondent competent to stand trial and lifted the suspension. An order was filed on November 18, 1987, to that effect. On May 13, 1988, the day scheduled for trial, respondent filed a motion stating that none of the tolling provisions of Rule 5-604(B) applied and that no extension of time had been sought by the State and granted by the supreme court. See SCRA 1986, 5-604(B), (C), and (D).
On appeal, the State argued that the tolling provision applicable to the present case is found in Rule 5-604(B)(2) which provides for a stay “on a finding of incompetency to stand trial.” The State maintained that, even though a stay in proceedings for the purpose of determining competency, as opposed to a finding of incompetency, does not fall within the literal language of the Rule, it is sufficiently analogous to recommence the six-month time period on November 18, 1987, when the trial court found Mendoza competent to stand trial and lifted the suspension. The court of appeals disagreed and read the rule in accordance with its plain meaning. In affirming the trial court, the appellate court opined:
In this case there was never a finding of incompetency; therefore, unless we are to read language into the rule which is not present, the trial must have commenced six months after the date of the arraignment, which took place on November 25, 1986. Since the trial was not scheduled to commence until May 13, 1988, almost one year after the six-month rule had run, the trial court had no alternative but to dismiss the information with prejudice. [Citations omitted.]
Moreover, the court reasoned the State could have applied for an extension of time under subsection C of the Rule.
We do not agree with this hyper-technical analysis of our six-month speedy trial rule. The court of appeals’ analysis fails to consider the extensive procedures we have set forth in Rule 5-602(B), SCRA *4481986, 5-602(B), to determine the competency of a defendant to stand trial. When looking at these procedures in their entirety, the delay to evaluate the competency of a defendant is essential in protecting his rights. We reverse the court of appeals and the district court, and reinstate the information against Mendoza.
[T]he right to [a] speedy trial is fundamentally a right guaranteed by federal and state constitutions, but it is also a statutory right in those states which in addition to the constitutional guaranty define the nature and limits of the right by express statute. Therefore, waiver or loss by one accused of [a] crime of his right to a speedy trial includes waiver or loss not only of such right as it is guaranteed generally by federal and state constitutions but also of the rights of [an] accused under statutes attempting to define “speedy trial” by providing for the time within which [the] accused must be brought to trial.
Many states have enacted statutes providing a time limit upon delay of trial and these statutes are held to be supplementary to the constitutional provisions for [a] speedy trial and enacted to give them form and force____
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Generally speaking, a speedy trial is one conducted according to prevailing rules, regulations, and proceedings of law free from arbitrary, vexatious and oppressive delays. The right does not require a trial immediately upon return of an indictment, nor on arrest made under it, but requires that the trial shall be had as soon as reasonably possible after the indictment is found, without depriving the prosecution of a reasonable time in which to prepare for trial. [Citations omitted.]
Annotation, Waiver or Loss of Accused’s Bight to Speedy Trial, 57 A.L.R.2d 302, 305 (1958).
The right to a speedy trial is grounded in the sixth and fourteenth amendments of the United States Constitution and in Article II, Section 14 of the New Mexico Constitution. In addition, the right in New Mexico is found in Rule 5-604, which provides in relevant part:
B. Time Limits for commencement of trial. The trial of a criminal case ... shall be commenced six (6) months after whichever of the following events occurs latest:
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(2) if the proceedings have been stayed on a finding of incompetency to stand trial, the date an order is filed finding the defendant competent to stand trial.
We agree that the State’s interpretation of Rule 5-604 to allow a recommencement of the six-month period following a stay to determine competency is consistent with the intent of the rule, with the interests protected by it, and is appropriate in the present case. This court has stated that the purpose of the six-month time period in which to commence the trial of an accused is “to assure the prompt trial and disposition of criminal cases” and is not to be technically applied “to effect dismissals.” State v. Flores, 99 N.M. 44, 46, 653 P.2d 875, 877 (1982); accord State v. Benally, 99 N.M. 415, 419, 658 P.2d 1142, 1146 (Ct.App.1983). Therefore, the rule “is to be read with common sense.” Flores, 99 N.M. at 46, 653 P.2d at 877.
In applying this “common sense” approach to the situation in Flores, we interpreted the six-month speedy trial rule, NMSA 1978, N.M.R.Crim.P. 37 (Repl.Pamp. 1980), to start running anew from the date of defendant’s arrest after defendant failed to appear at the pretrial conference. Similarity in Benally, the court of appeals utilized a common sense analysis to permit recommencement of the six-month time period upon filing an amended information that added an entirety new offence to the charges. In both cases a literal interpretation of our six-month speedy trial rule would not have allowed that result nor effectuated the rule’s intent and purpose. Cf. State v. Felipe V., 105 N.M. 192, 730 P.2d 495 (Ct.App.), cert. denied, 105 N.M. 111, 729 P.2d 1365 (1986) (under Children’s Court Rules, review of a writ by a higher court is an appeal recommencing the adjudicatory hearing within ninety days of ser*449vice of petition on juvenile or of later appeal); State v. Padilla, 92 N.M. 19, 582 P.2d 396 (Ct.App.), cert. denied, 92 N.M. 180, 585 P.2d 324 (1978) (although not expressly stated in the Children’s Court Rules speedy trial provisions, these provisions are tolled during the appellate proceedings reversing the trial court’s dismissal of the supplemental information).
In the present case, a motion to determine Mendoza’s competency and a suspension of the proceedings was agreed to by both sides. The period of time to make this determination must be excluded from determination of the period for commencement of trial. The law is clear that conviction of a legally incompetent accused violates due process. See Pate v. Robinson, 383 U.S. 375, 86 S.Ct. 836, 15 L.Ed.2d 815 (1966). And one who is incompetent cannot stand trial. See SCRA 1986, 5-602(B)(3). Therefore, until obtaining the result from the examination, a trial court has no choice but to delay the trial and stay the proceedings. During the time an accused’s competency is being assessed, he or she is unavailable for trial. Regardless of who initiates the proceeding a competency examination is clearly on behalf of the accused and in no way infringes on that person’s speedy trial rights. See Commonwealth v. Millard, 273 Pa.Super. 523, 532, 417 A.2d 1171, 1175-76 (1979); accord State v. Starcevich, 139 Ariz. 378, 389, 678 P.2d 959, 970 (Ct.App.1983); Jones v. People, 711 P.2d 1270, 1281 (Colo.1986); Andrews v. State, 441 N.E.2d 194, 199 (Ind.1982); State v. Lewis, 220 Kan. 791, 796, 556 P.2d 888, 892 (1976); ABA Standards for Criminal Justice § 12-2.3(a) (1980) (period of delay resulting from examination of defendant’s competency should be excluded from speedy trial computation).
The same principles which support a recommencement of our six-month rule following a stay based upon a finding of incompetency, SCRA 1986, 5-604(B)(2), support restarting the time period after proceedings have been stayed to determine an accused’s competency. In both situations, the delay is clearly for the benefit of the defendant who cannot stand trial until the issue of competency has been properly assessed. These delays are chargeable to the defendant and must be excluded from any speedy trial analysis. A common sense approach of Rule 5-604(B)(2) mandates this interpretation.
Moreover, in the present case, the trial court ordered a suspension of proceedings to which both parties agreed. The concurrence or stipulation of both the State and respondent to a suspension of the proceedings to determine competency is sufficiently analogous to the incompetency provisions of Rule 5-604(B)(2) to warrant automatic recommencement upon a subsequent determination of competency. In this case, we are inclined to infer that suspension or stay of the proceedings contemplated a suspension of Rule 5-604 with recommencement of the six months upon the lifting of the stay. Nothing in the trial court’s order indicated that the six-month rule would continue to run during the time required to complete the mental examination of respondent. Moreover, defense counsel’s reservation of his client’s rights when the suspension of the proceedings was lifted in November 1987 must be evaluated in light of its untimeliness and his concession that it was unclear whether the suspension did not fall within the provisions of 5-604(B)(2).
This, however, does not end our inquiry. Whenever there is a delay of more than six months between the time of arraignment and the date of the trial, four factors are to be considered in determining whether a defendant has been denied the right to a speedy trial. State v. Chacon, 103 N.M. 288, 289, 706 P.2d 152, 153 (1985). These are length of delay, reason for delay, defendant’s assertation of his right, and ensuing prejudice to the defendant. Id.; see also Barker v. Wingo, 407 U.S. 514, 92 S.Ct. 2182, 33 L.Ed.2d 101 (1972).
Mendoza was arraigned on November 25, 1986, and scheduled to stand trial on May 13, 1988. This was approximately an eighteen-month delay. This delay, however, was for Mendoza’s benefit to assess his competency to stand trial. The record indicates he acquiesced to a stay in the proceedings during determination of his *450competence. Further, respondent did not assert his right to a speedy trial until the day the trial began, six months after the trial court lifted the stay. Given respondent's responsibility for the delay, his failure to assert his rights, and the absence of any identifiable prejudice, we find no violation of the right to a speedy trial.
We reverse the court of appeals and the district court, and remand this case to the district court to reinstate the information.
IT IS SO ORDERED.
SCARBOROUGH and BACA, JJ., concur.
RANSOM, J. (specially concurring).
SOSA, C.J. (dissenting).