OPINION
This appeal challenges the first degree murder convictions of Bryan McCrary and Bart D. Burdick.
McCrary had attended a carnival in Hobbs and felt he was cheated out of sixty-four dollars. He and Burdick decided they would get revenge by shooting the tires of the carnival trucks. Armed with two .22 caliber rifles, two 30-30 caliber rifles, a shotgun, and accompanied by William Sutton, they returned to the carnival site at 1:30 a.m.
With Burdick driving, the group contend they circled the area two to three times in a pick-up truck. Stopping momentarily and then driving along slowly, they discharged about twenty-five shots into several tractor-trailers and cabs. Loretta DeGracia was in a sleeper cab of one of the trucks. Curtains were pulled in the windows above the bed. She was killed by a high-caliber bullet in the head.
We first address the issues raised by both appellants. McCrary and Burdick claim: (a) the evidence does not support first degree murder convictions; (b) they were denied a speedy trial; and (c) the trial court’s refusal to instruct on second degree murder was in error.
McCrary and Burdick contend that the evidence does not support a finding that they acted with a “depraved mind regardless of human life.” NMSA 1978, § 30-2-1(A)(3) (Cum.Supp.1983). McCrary adds that a first degree murder conviction must be supported by evidence that he had a subjective knowledge that his act was greatly dangerous to the lives of others. *673He argues that the circumstances support only a second degree conviction because they demonstrate an objective knowledge.
McCrary alleges that a subjective knowledge that the shooting would be dangerous to any person within the truck is negated because they waited until they thought all people had left the carnival, circled two or three times to make sure no one would get hurt, and they only intended to shoot the tires. Also, a police detective indicated that all mobile homes and campers were located a hundred feet from the damaged trucks. The campers and mobile homes were not struck by the shots.
The standards of proving the defendant’s culpable knowledge for a depraved mind murder are given in the Uniform Jury Instructions, 2.05 and 2.10. Instruction 2.05 states:
The defendant is charged with first degree murder by an act greatly dangerous to the lives of others indicating a depraved mind without regard for human life. For you to find the defendant guilty ..., the state must prove to your satisfaction beyond a reasonable doubt each of the following elements of the crime:
4. The defendant knew that his act was greatly dangerous to the lives of others____
NMSA 1978, UJI Crim. 2.05 (Repl.Pamp. 1982). But to prove the lesser included offense of second degree, Instruction 2.10 requires the state to prove “[t]he defendant knew that his acts created a strong probability of death or great bodily harm to [name of victim] [or any other human being].” NMSA 1978, UJI Crim. 2.10(2) (Repl.Pamp.1982) (footnotes omitted).
The committee commentary to the Uniform Jury Instruction 2.05 provides that the first degree depraved mind murder instruction sets forth a subjective test while second degree murder requires an objective test. The committee commentary is persuasive authority, although it is not binding on this Court. Rutherford v. Darwin, 95 N.M. 340, 622 P.2d 245 (Ct.App.1980).
We agree that the first degree instruction requires a subjective knowledge. However, the knowledge is not that asserted by McCrary. Defendants did not have to actually know that DeGracia was in the sleeper compartment. Rather, sufficient subjective knowledge exists if Defendants’ conduct was very risky, and under the circumstances known to Defendants they should have realized this very high degree of risk. See W. LaFave & A. Scott, Jr., Handbook on Criminal Law § 70 (1972).
As is generally the case in a first degree murder case, the element of intent is seldom susceptible to direct proof and accordingly may be proved by circumstantial evidence. State v. Manus, 93 N.M. 95, 98, 597 P.2d 280, 283 (1979). Seldom will an accused admit at trial that he actually knew his acts placed another’s life in great danger. In these instances, the jury decides whether there is a subjective knowledge of risk by considering “what the defendant should realize to be the degree of risk, in the light of the surrounding circumstances which he knows____” W. LaFave & A. Scott, Jr., supra, at 542.
There is reasonable support in the evidence for the jury to find that Defendants knew their act was greatly dangerous to the lives of others. Although Defendants claim that they only intended to shoot the tires, and not to harm anyone, the jury could disregard their claim. Not a single tire was shot, yet there were twenty-five bullet holes in the upper parts of the vehicles. In light of the surrounding circumstances, Defendants should have realized the risk of someone sleeping in the sleeper compartment. McCrary and Burdick repeated several times that they only wanted to shoot low lest they injure someone. Also, they contemplated slashing the tires but this plan was rejected because of the danger of being caught. This testimony supports a jury determination that Defendants had reason to know people were in the area. We will not consider the weight of *674the evidence if substantial evidence supports the verdict. See State v. Lankford, 92 N.M. 1, 582 P.2d 378 (1978). Accordingly, we affirm the jury’s finding of first degree murder.
Each defendant claims a violation of his right to a speedy trial under NMSA 1978, Crim.P.Rule 37 (Cum.Supp.1983). Rule 37 requires that an indictment or information be dismissed with prejudice if trial of any person does not commence within six months, inter alia, after the charges are filed, after the mandate of an appeal is filed, or within an extension granted by the Supreme Court. Eighteen months passed between Defendants’ arrest and trial. This delay triggers an inquiry into the factors balanced to ascertain whether one’s right to a speedy trial was violated. State v. Tafoya, 91 N.M. 121, 570 P.2d 1148 (Ct.App.1977).
The four factors that must be weighed are the "length of delay, the reason for the delay, the defendant’s assertion of his right and prejudice to the defendant.” State v. Harvey, 85 N.M. 214, 215-16, 510 P.2d 1085, 1086-87 (Ct.App.1973); see also Barker v. Wingo, 407 U.S. 514, 92 S.Ct. 2182, 33 L.Ed.2d 101 (1972). Contrary to Defendants’ assertion, we do not find an unjustified delay which compels relief.
On April 25, 1981, Defendants were charged with an open charge of murder. In June, Magistrate Judge Hallam ordered that they be bound over for trial in the district court for “2d Degree Murder or lesser Offense.” In disregard of the bind-over order, State filed an information charging defendants with first degree murder. In July, Defendants moved to dismiss the information because it did not conform to the bind-over order. This motion was denied. Defendants filed an interlocutory appeal on September 15, 1981. In January 1982, the court of appeals reversed the trial court, holding that “the information must charge substantially the same offense as that charged by the magistrate.” State v. McCrary, 97 N.M. 306, 312, 639 P.2d 593, 599 (Ct.App.1982).
In January 1982, prior to the court of appeals ruling, State obtained from this Court an extension of the six-month requirement under Rule 37. The petition was joined by opposing counsel’s stipulation. This Court granted until July 1982 to bring the matter to trial. After the court of appeals mandate was issued, trial was scheduled for June 8, 1982.
On May 26, 1982 State filed nolle proseguís to dismiss its informations, which charged second degree murder. A grand jury indictment was acquired in August 1982. Defendants were charged with first degree murder. Trial commenced on October 27, 1982 and on October 28, the jury returned a verdict of guilty of first degree murder.
First, the delay, occasioned by Defendants’ resistance to a first degree murder charge, and their interlocutory appeal, does not impugn bad motives to State as a denial of Defendants’ right to a speedy trial. We are not penalizing Defendants for exercising their right of appeal, or for securing their rights to be charged according to the bind-over order. Rather, we simply conclude that this time lapse was justified and cannot be charged against State for the speedy trial calculation.
Second, Defendants certainly cannot complain of the time lapse due to the stipulated extension. By agreeing to the extension, they failed to assert their right to a speedy trial from January until July 1982.
Third, Defendants allege that the nolle proseguís were not filed in good faith, and that the dismissals were sought only to gain a tactical advantage. Citing United States v. Lara, 520 F.2d 460 (D.C.Cir.1975), Defendants allege that delay caused by tactical maneuvering requires that the time between filing to dismiss and the grand jury indictment must be counted for purposes of Rule 37. However, Lara is distinguishable from the instant case. In Lara, the prosecution moved to dismiss charges against defendants in the District of Columbia for violating the narcotics laws. Subsequently, an indictment alleging sub*675stantially the same charges was obtained in the Southern District of Florida. The court found that the tactic was employed because the prosecution believed Florida would be more sympathetic to its case. A nineteen-month delay resulted. The speedy trial guarantee was violated because the court found the delay to be unconscionable and unjustified.
Here, however, the maneuvering was not done to get a tactical advantage. The bind-over order required a charge of second degree murder or less. The State, since July 1981, maintained that first degree murder was the appropriate charge. It is generally easier to prove second degree than first because the former is a lesser included offense. NMSA 1978, § 30-2-l(B) (Cum.Supp.1983). The nolle prosequis were necessary so State could prosecute for what it long maintained as the appropriate crime. This was not bad faith. For good cause, State may terminate and reinstitute a criminal prosecution. See State ex rel. Delgado v. Stanley, 83 N.M. 626, 495 P.2d 1073 (1972).
The speedy trial guarantee is to prevent lengthy incarceration prior to trial, to reduce impaired liberty while an accused is released on bail, and to shorten the disruption of life caused by pending and unresolved criminal charges. United States v. MacDonald, 456 U.S. 1, 8, 102 S.Ct. 1497, 1502, 71 L.Ed.2d 696 (1982). Accordingly, once charges are dropped in good faith, the delay is not scrutinized by the speedy trial clause of the Sixth Amendment of the federal constitution. Id. at 7, 102 S.Ct. at 1501. During the interval between dismissal and the first degree murder indictment, Defendants were not in custody. The bonds were discharged and Defendants were released without prejudice. The time period from May 26 to August 27, 1981 is not attributable to State as delay, denying a speedy trial. Although trial took place eighteen months after Defendants’ arrest, we find no violation of the right to a speedy trial.
Defendants argue that the trial court erred in failing to give State’s requested instruction on second degree murder as a lesser included offense. When State submitted the instruction, counsel for Defendants objected. By objecting, Defendants have waived any error that might have occurred. As we stated in State v. Trujillo, 27 N.M. 594, 603, 203 P. 846, 849 (1921), with regard to submitting jury instructions for the court, “It will be available error only in case the court fails to agree with [defendant’s trial] counsel as to the proper scope of the instructions.” See also State v. Najar, 94 N.M. 193, 196, 608 P.2d 169, 172 (Ct.App.1980). Here, the trial court concurred with Defendants’ position; it did not “fail to agree.” They cannot now complain that it was reversible error. Cf. State v. Doe, 672 P.2d 654 (1983) (failure to instruct on general criminal intent was not jurisdictional error requiring automatic reversal, where respondent did not tender such instruction or object to not giving the instruction); and State v. Garcia, 46 N.M. 302, 128 P.2d 459 (1942) (defendant acquiesced in the trial court’s instructions and could not claim initially on appeal that such instructions were improper).
Burdick separately disputes an alleged prosecutorial failure to rebut his own witness’s statement which tended to exculpate defendants, while McCrary contends the trial court erroneously precluded cross-examination into Sutton’s juvenile adjudication and that it erred in refusing admission of a police report. We find these other issues raised by Defendants to be without merit.
For the reasons given, the trial court and jury conviction of first degree murder is affirmed.
IT IS SO ORDERED.
FEDERICI, C.J., and RIORDAN and STOWERS, JJ., concur.
SOSA, Senior Justice, respectfully dissenting.