Records obtained by The Associated Press show that Hixon was previously the focus of a separate police investigation after being accused of what is being described as "inappropriate touching" back in 2014. At the time, Hixon denied the allegations and told police he was stressed the affirmations would hurt his political vocation. It is not clear whether the new investigation launched past year is connected to the 2014 allegations.
The AG's Office had no comment Tuesday on what now happens to the investigation.
Hixon was in his third term, which would have ended on November 30, 2018.
"I hope that my efforts have helped improve the lives of my constituents in District 10, as well as all Idahoans", Hixon wrote when he abruptly resigned from his post.
After his resignation, Hixon was arrested twice on suspicion of driving under the influence, on December 9 and December 30, and for resisting arrest the first time when police claimed he refused to pull over and exit his vehicle.
Last year, Hixon and his wife Danielle divorced.
Across the country, sexual harassment allegations have surfaced in government, entertainment and business, leading to resignations and policy changes. The House's chaplain then led lawmakers in prayer.
"We are all asking ourselves what we could have done to help in the lead-up to this", House Speaker Scott Bedke said.
Brandon Hixon was found dead by a family member at his home in Caldwell, Idaho Tuesday.
Bedke later said the House will likely organize some sort of financial relief for Hixon's family, but said it was too early to say what exactly was planned.
Other lawmakers also offered condolences. "I wish I had taken after the promptings I got and called with expressions of generosity and support", said Rep. Bryan Zollinger, R-Idaho Falls, in a tweet. "Reminder to us all to love one another despite differences of opinion". Expectation you discover some peace, Brandon. "Condolences and prayers to his family including his children".