He could be charged as a juvenile for Harassment.
565.090. 1. A person commits the crime of harassment if he or she:
(1) Knowingly communicates a threat to commit any felony to another person and in so doing frightens, intimidates, or causes emotional distress to such other person; or
(2) When communicating with another person, knowingly uses coarse language offensive to one of average sensibility and thereby puts such person in reasonable apprehension of offensive physical contact or harm; or
(3) Knowingly frightens, intimidates, or causes emotional distress to another person by anonymously making a telephone call or any electronic communication; or
(4) Knowingly communicates with another person who is, or who purports to be, seventeen years of age or younger and in so doing and without good cause recklessly frightens, intimidates, or causes emotional distress to such other person; or
(5) Knowingly makes repeated unwanted communication to another person; or
(6) Without good cause engages in any other act with the purpose to frighten, intimidate, or cause emotional distress to another person, cause such person to be frightened, intimidated, or emotionally distressed, and such person's response to the act is one of a person of average sensibilities considering the age of such person.
2. Harassment is a class A misdemeanor unless:
(1) Committed by a person twenty-one years of age or older against a person seventeen years of age or younger; or
(2) The person has previously pleaded guilty to or been found guilty of a violation of this section, or of any offense committed in violation of any county or municipal ordinance in any state, any state law, any federal law, or any military law which, if committed in this state, would be chargeable or indictable as a violation of any offense listed in this subsection.
In such cases, harassment shall be a class D felony.
3. This section shall not apply to activities of federal, state, county, or municipal law enforcement officers conducting investigations of violation of federal, state, county, or municipal law.
You are making the right decision to go to an attorney and get the phone records. Make sure to have the text message transcriptions too. Showing that this was in response to the other child's harassment will be helpful and possible justify his actions.
Please reply if I can help further.
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