On Tuesday, March 18, 2025, the Presiding Disciplinary Judge of the Colorado Supreme Court suspended attorney Peter Lederer Mattisson for one year and one day. The suspension is effective immediately. To be reinstated to the practice of law, Mattisson must demonstrate by clear and convincing evidence that he has undergone rehabilitation, complied with all disciplinary orders, and is fit to practice law.
The case is entitled “In the Matter of Peter Lederer Mattisson,” with case number 25PDJ7.
The suspension follows serious criminal charges against Mattisson, stemming from two incidents of domestic violence. In December 2022, he was involved in an altercation where he physically assaulted his spouse, knocking her to the ground. A subsequent incident in May 2023 escalated when he strangled her in a headlock, continuing the assault as she fell.
In September 2023, Mattisson faced additional legal troubles when he was arrested for violating a mandatory protection order. He admitted to sending text messages to his spouse, which directly contravened the order. This charge was later dismissed as part of a global settlement agreement after he pleaded guilty to a third-degree assault charge, classified as a misdemeanor involving domestic violence. Following this plea, Mattisson received a deferred judgment of twelve months, which includes conditions such as attending domestic violence evaluation and treatment, writing an apology letter to the victim, and adhering to the protective order. He is also prohibited from possessing weapons and committing further legal violations.
Compounding his legal issues, Mattisson failed to report his conviction to the disciplinary authorities within the required fourteen-day period, as stipulated by C.R.C.P. 242.11(c)(1). His actions were found to be in violation of several Colorado Rules of Professional Conduct (Colo. RPC), including knowingly disobeying obligations under tribunal rules, committing criminal acts that reflect adversely on his honesty and fitness, and engaging in conduct that harms others.
According to Avvo, Mr. Mattisson is bankruptcy and debt attorney in Westminster, Colorado. He acquired his law license in Colorado in 1977.
A copy of the original filing can be found here.
