(CNN) The Montana Democratic Party filed complaints with two congressional ethics watchdogs Thursday regarding Republican Rep. Greg Gianforte's assault of a reporter and subsequent actions last year.

In letters to the House Committee on Ethics and the Office of Congressional Ethics, the state party's executive director, Nancy Keenan, asked for an investigation into whether Gianforte "violated House Ethics Rules by making false statements to the police and the public" about the assault, "thereby failing to 'conduct himself at all times in a manner that shall reflect creditably on the House.'"

"There is a protocol and a conduct becoming of a member of Congress, and he has not held to that level of conduct, and that's the bottom line," Keenan told CNN.

The complaints, previously reported by the Associated Press, were filed on the one-year anniversary of Gianforte's altercation with Guardian reporter Ben Jacobs. Gianforte was charged with and pleaded guilty to misdemeanor assault for body-slamming Jacobs and breaking his glasses the night before Montana's 2017 special election

Gianforte's campaign initially blamed the incident on Jacobs' "aggressive behavior" and offered a version of events at odds with the audio recording and statements of witnesses. Documents reviewed by the Bozeman Daily Chronicle and referenced in the complaints indicate that when questioned immediately after the incident, Gianforte told investigators that the reporter was to blame for altercation.

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