Defendant, Timothy Milner, was convicted of threat of arson based on statements he made to employees of the Department of Employment Services (DES) between June 13 and June 16, 1995. See Iowa Code § 712.8 (1995). He appeals, claiming (1) the evidence was insufficient to support his conviction, and (2) the statute under which he was convicted is overbroad and vague. We find substantial evidence in the record to support Milner’s conviction of threatening arson and we detect no constitutional infirmity in section 712.8. Therefore, we affirm.
I. Background Facts and Proceedings.
In June of 1995, DES denied unemployment benefits to Milner. Milner went to a Des Moines office of DES and talked with a DES interviewer, Tom Saylor. Milner was visibly angry and, using profanity, expressed dissatisfaction with the decision made by DES on his claim. As he left, he said to Saylor, “Just remember what happened in Oklahoma City.” 1 Saylor viewed this statement as a threat and reported the incident to the Des Moines police.
Three days later Milner telephoned DES and spoke with DES employee Ann Morris. Milner was still angry and told Morris, “I’ll use the last of my gas money to come down and blow the place up.” Several times during Milner’s fifteen-minute conversation with Morris he said he would “drive in his truck and come blow [them] away.”
Morris transferred Milner’s call to her supervisor, Glen Howard. Milner continued to be very agitated and upset during his conversation with Howard. He spoke to Howard for forty-five minutes, expressing his dissatisfaction with DES and telling Howard what he — Milner—might or would do about his complaints. Milner said, among other things, that he would come to the DES office with a hatchet and that he would drive his truck into their building. During a later phone conversation between Milner and Howard, Milner said, “I’m not going to be responsible for my behavior if you continue to aggravate me.” Milner also told Howard “someone might get hurt” and it is “not going to be pretty if I have to come down there.” These conversations were reported to the police.
The DES staff was very concerned about Milner’s statements. Based on the content of Milner’s statements, his tone of voice, and his agitated state, DES employees believed Milner was desperate and a threat to their safety. DES formed a security committee, *10 hired a security consultant, and installed a security system.
Based on these events, the State filed a trial information charging Milner with threatening to commit arson in violation of Iowa Code section 712.8. Milner’s pretrial motion to dismiss the charge on the basis that section 712.8 was unconstitutionally overbroad and vague was overruled.
Milner waived jury trial, and the case was submitted to the district court on a stipulated record consisting of the police reports, the depositions of witnesses, and the documents submitted in connection with the motion to dismiss. The district court found Milner guilty of the charge of threat of arson and sentenced him to five years imprisonment, suspending the sentence and placing Milner on two years probation. Milner brings this appeal.
We start our analysis with an interpretation of section 712.8 and consideration of whether the evidence was sufficient to support the trial court’s decision that Milner violated the statute. We will then determine whether there is any merit to Milner’s constitutional challenges to the statute as we have interpreted and applied it.
II. Sufficiency of the Evidence.
A. Interpretation of the statute. Milner was convicted of violating Iowa Code section 712.8:
Any person who threatens to place or attempts to place any incendiary or explosive device or material, or any destructive substance or device in any place where it will endanger persons or property, commits a class “D” felony.
Iowa Code § 712.8. Although we have never interpreted section 712.8 before, we have considered the meaning of the words “threaten” and “threat” in connection with other criminal statutes.
In prior cases interpreting the words “threaten” or “threat,” we have applied the common meaning of those words. In
State v. Crone,
We think the same interpretation of “threaten” and “threat” applies here. Section 712.8 prohibits a person from expressing an intention to place an incendiary, explosive, or destructive device or material in a place where it will endanger persons or property. The prohibited statements must be understandable as a threat by a reasonable person of ordinary intelligence. Interpreted in this way, the statute encompasses only true threats and does not reach expressions that a reasonable person would understand as a joke, idle talk, or mere statements of political hyperbole.
B.
Sufficiency of the evidence.
In considering Milner’s sufficiency-of-the-evidence claim, we view the record in the light most favorable to the State.
State v. Fratzke,
Milner contends his statement, “Just remember what happened in Oklahoma City,” is not a threat by him to use an incendiary or explosive device. But Milner did not make a vague and isolated reference to the Oklahoma City bombing. Over a five-day period, he made, in an angry and threatening tone of voice, the following statements:
1. Just remember what happened in Oklahoma City.
*11 2. I’ll use the last of my gas money to come down and blow the place up. 2
3. I’ll drive in my truck and come blow you away.
4. I’m not going to be responsible for my behavior if you continue to aggravate me.
5. Someone might get hurt.
6. It is not going to be pretty if I have to come down there. 3
A reasonable person of ordinary intelligence could construe these statements, considered in the context and manner in which they were made, as serious expressions of an intention to place an “explosive device or material” where it will harm people or property. As we have stated before, “[tjhreats need not be explicit; they may be made by innuendo or suggestion. It is only necessary that the threat be definite and understandable by a reasonable person of ordinary intelligence.”
Crone,
Substantial evidence supports the trial court’s finding that Milner threatened to use an explosive device in or near the DES budding, including the testimony of the witnesses as to the specific words spoken by Milner, Milner’s dissatisfaction and anger over the denial of his claim for unemployment benefits, his threatening tone of voice, and his agitated demeanor. Therefore, we reject Milner’s claim the evidence was insufficient to support his conviction.
III. Preservation of Error on Constitutional Issues.
Before we consider Milner’s constitutional claims on the merits, we must first deal with the State’s contention Milner failed to preserve error on these claims because they were raised in an allegedly tardy pretrial motion to dismiss. The State relies on Iowa Rule of Criminal Procedure 10(4), which provides, in part, that pretrial motions under rule 10(2) “shall be filed when the grounds therefor reasonably appear but no later than 40 days after arraignment.” Mil-ner’s motion was filed fifty-five days after his arraignment.
We begin our analysis with an examination of rule 10(2):
Any defense, objection, or request which is capable of determination without the trial of the general issue may be raised before trial by motion. The following must be raised prior to trial:
[The rule then lists seven categories of defenses, objections, motions and requests.]
Iowa R.Crim. P. 10(2) (emphasis added). The matters included in the “must-be-raised” list do not include claims that the statute under which the defendant was charged is unconstitutional.
We interpret rule 10(2) as creating two categories of defenses and objections that are the subject of pretrial motions to dismiss: (1) those that “may” be raised by pretrial motion, and (2) those that “must” be raised by pretrial motion. To hold that a defendant must raise
all
objections and defenses no later than forty days after arraignment would render the list following the second sentence of section 10(2) meaningless.
See id.
(naming only seven categories of defens
*12
es, objections, motions and requests that “must” be raised prior to trial);
see also State v. Ahitow,
Our conclusion that the forty-day limitation of rule 10(4) does not apply here is not the end of our inquiry, however. We have held that a pretrial motion under rule 10(2) is the proper vehicle to use when challenging the constitutionality of a statute, and that such a challenge must be raised “at the earliest opportunity in the progress of the case.”
State v. Munz,
Milner filed his motion to dismiss challenging the validity of section 712.8 twenty-four days after the completion of discovery and twenty-four weeks before trial. He contends depositions of the State’s witnesses were necessary to formulate and support his argument that section 712.8 was unconstitutional as applied in this case. (We note the minutes of testimony filed with the trial information were nonspecific as to the statements Milner allegedly made and the minutes simply incorporated “any matters made known to the defendant through discovery and/or depositions in this case.”)
We conclude Milner’s motion to dismiss adequately preserved his constitutional claims. Under the circumstances of this case, Milner, in filing his motion twenty-four days after the completion of discovery, raised the constitutional issues at the earliest available opportunity. We also note the objectives of our error-preservation rules were accomplished; opposing counsel had adequate time to respond and the trial court had ample opportunity to rule before the trial twenty-four weeks later. Because Milner preserved error on his claim that section 712.8 is constitutionally infirm, we now address the merits of that claim.
IV. Constitutional Challenges to Section 712.8.
A.
Standard of review.
Milner claims section 712.8 is unconstitutionally overbroad and vague as applied to his conduct.
See
U.S. Const, amends. V, XIV. We review constitutional claims de novo.
State v. Huisman,
B.
Overbreadth.
“The First Amendment to the United States Constitution prohibits Congress from making any law ‘abridging the freedom of speech.’ ”
State v. McKnight,
*13
The First Amendment’s guarantee of freedom of speech prevents states from punishing “the use of words or language not within ‘narrowly limited classes of speech.’ ”
Gooding v. Wilson,
Because we have now defined “threats” as an
expression
of an intention to inflict injury or damage on another, section 712.8 clearly regulates speech.
See Wurtz v. Risley,
In
Watts v. United States,
Some courts have interpreted
Watts
as identifying another category of speech not protected by the First Amendment — true threats.
E.g., Melugin v. Homes,
Milner claims that an interpretation of section 712.8 that would encompass his statements necessarily results in an over-broad statute because his statements were not true threats, but were political speech protected by the constitution.
See Buckley v. Valeo,
In relying on
Fratzke,
Milner overlooks that the statements of dissatisfaction made in that case contained no fighting words or threats. In contrast, Milner’s statements were not mere expressions of dissatisfaction with government employees; they were, as the trial court found, threats to place an explosive device in or near the DES building.
See Melugin,
We have interpreted section 712.8 as reaching only true threats, not political speech. Our application of this statute to Milner’s statements to DES employees is not at odds with this interpretation. Accordingly, section 712.8 is not impermissibly over-broad.
See Melugin,
C.
Vagueness.
Milner also argues section 712.8 is vague as applied to his conduct.
5
“As generally stated, the void-for-vagueness doctrine requires that a penal statute define the criminal offense with sufficient definiteness that ordinary people can understand what conduct is prohibited and in a manner that does not encourage arbitrary and discriminatory enforcement.”
Kolender v. Lawson,
Milner complains that he had no way of knowing that his “vague reference to the Oklahoma City bombing” could be construed (1) as a threat, and (2) as referring to the use of an explosive. He points out the statute does not define the terms “threaten” and “explosive device.”
“Despite the lack of an express definition, a statute is not unconstitutionally vague if the meaning of the words used can be fairly ascertained by reference to their ordinary and usual meaning, the dictionary, similar statutes, the common law, or previous judicial determinations.”
Osmundson,
When the common meaning of the words used in section 712.8 are applied to Milner’s conduct, it is obvious his statements fall within the prohibitions of the statute. As we pointed out earlier, Milner’s statements went beyond a casual, isolated, and obscure reference to the bombing of a federal building in Oklahoma City. Considering his statements in the context in which they were made, a reasonable person would understand that Milner was threatening to blow up the DES building with a truck bomb, an explosive device.
See Bellrichard,
V. Summary.
Section 712.8 proscribes statements that a reasonable person of average intelligence would construe as an expression of intention to place an incendiary, explosive, or destructive device or material in a place where it will harm people or property. There was substantial evidence to support the trial court’s finding that Milner violated the statute.
True threats, the speech proscribed by section 712.8, are not constitutionally protected. Because the statute reaches only speech the State may regulate, the statute is not impermissibly overbroad. Nor is section 712.8 vague as applied to Milner’s conduct, which clearly falls within the scope of the statute. Finding no error, we affirm.
AFFIRMED.
Notes
. On April 19, 1995, a truck bomb exploded near the Alfred P. Murrah Federal Building in Oklahoma City, killing 168 and wounding 600.
. Milner challenges the accuracy of the trial court's finding that Milner said he would "use the last of [his] gas money and come down and blow the place up." This statement was recorded in the supplemental police report filed during the police investigation of this incident. This report was part of the stipulated record before the court and therefore is substantial evidence supporting the trial court’s finding this statement was made.
. The parties dispute whether the State may rely on a statement allegedly made by Milner to DES employee Howard that Milner would "back up a truck full of explosives and blow up the facility.” We do not consider this statement in deciding the issues before us and therefore find it unnecessary to determine whether the alleged absence of this statement in the trial information precluded the State from using it to prove Milner’s guilt.
. The defendant stated, "And now I have already received my draft classification as 1-A and I have got to report for my physical this Monday coming. I am not going. If they ever make me carry a rifle the first man I want to get in my sights is L.B.J.”
Watts,
. Milner's vagueness claim is founded on the due process clauses of the Iowa and United States Constitutions.
See Kolender v. Lawson,
