People v. Mattisson.
No. 25PDJ7. 3/18/2025. Stipulation to Discipline.
April 30, 2025
The Presiding Disciplinary Judge approved the parties’ stipulation to discipline and suspended Peter Lederer Mattisson (attorney registration number 08396) for one year and one day, effective immediately. To be reinstated to the practice of law, Mattisson must prove by clear and convincing evidence that he has been rehabilitated, has complied with all disciplinary orders and rules, and is fit to practice law.
In July 2023, Mattisson was arrested at his home in Lafayette in connection with two separate domestic violence incidents in December 2022 and May 2023. In the first incident, Mattisson punched his spouse in her chest so hard he knocked her to the ground. In the second incident, he strangled her neck in a headlock, continuing to strangle her after she fell to the ground. Later, in September 2023, Mattisson was arrested and later charged for violating the mandatory protection order in his criminal case after he admitted to texting his spouse on two occasions that month. That charge was dismissed as part of a global settlement agreement in November 2023, when Mattisson pleaded guilty to one count of third-degree assault including an act of domestic violence, a class 3 misdemeanor. Mattisson received a 12-month deferred judgment. His sentence requires that he comply with the following conditions: attend domestic violence evaluation and treatment; write an apology letter to the victim; and comply with the protective order. In addition, Mattisson is prohibited from possessing weapons and from committing new law violations, including traffic infractions of four or more points.
Though CRCP 242.11(c)(1) required that Mattisson report the conviction to disciplinary authorities within 14 days, Mattisson did not report the conviction at any time.
Through this misconduct, Mattisson violated Colo. RPC 3.4(c) (a lawyer must not knowingly disobey an obligation under the rules of a tribunal); Colo. RPC 8.4(b) (it is professional misconduct for a lawyer to commit a criminal act that reflects adversely on the lawyer’s honesty, trustworthiness, or fitness as a lawyer in other respects); and Colo. RPC 8.4(h) (it is professional misconduct for a lawyer to engage in any conduct that directly, intentionally, and wrongfully harms others and that adversely reflects on the lawyer’s fitness to practice law).