This week, those same lawmakers said they are now considering throwing Patterson out of office after an ethics investigation uncovered a series of similar outbursts, along with other allegations, including that he once offered to give a lobbyist his vote in exchange for sex and that he regularly smokes marijuana.
The investigation came after prosecutors in Tucson charged Patterson with four misdemeanor counts of domestic violence. The charges, which he has pleaded not guilty to, stemmed from fights with his live-in girlfriend, who also happened to be his campaign manager at the time.
In late February, the woman went public with allegations that he dragged her from a car as she tried to drive away from their house during an argument.
It was the second time in two years a woman accused Patterson of domestic violence. In September 2010, the Tucson Weekly newspaper uncovered that his estranged wife had filed for a restraining order, saying he had been violent with her.
Patterson has refused to resign or apologize since the newest allegations began to surface.
However, he announced late Tuesday he was suspending his reelection campaign and "likely will not" seek a seat in the House again this year.
"I want focus on family, break from politics," he wrote in a message on Twitter.
Earlier in the week, he took a more defiant tone, taking to Twitter on Monday to defend himself against the latest report, which was put together by powerful Phoenix attorney Mike Manning and a team of investigators at the request of the House ethics committee.
"Manning report had pre-determined political outcome; based on lies & slams by politicians, lobbyists & lawyers," Patterson wrote in one post.
"Party politicians, media & lobbyists fear tough independence," he wrote in another. "I stir things up @ capitol but I don't mean to offend."
Patterson also announced on Twitter that he was leaving the Democratic Party to become an independent, saying "partisan politics," not his own behavior, was the problem.
The latest domestic violence allegations were what caused Patterson's fellow Democrats in the House to file an ethics complaint against him. But the latest incidents to be uncovered by the Manning investigation were even more startling.
One of Patterson's fellow Democrats, Rep. Margaret "Lynne" Pancrazi, told investigators she had taken to referring to him as "Dr. Jekyll and Mr. Hyde" and often described him as paranoid. Since the ethics complaint was filed, she said she and other lawmakers have been afraid to be around him.
"I have made a habit of keeping a weapon near me when I sleep," Pancrazi wrote in a signed declaration that was included in the report. "I fear for my safety at the Capitol and have requested additional security."
The ethics investigation also said Patterson had a history of being threatening and combative with his fellow lawmakers, cursing at them during committee hearings and yelling at them in the hallways of the state Capitol.
The report detailed an incident in which he allegedly called a male lawmaker an "asshole" and a "prick" and another in which he allegedly cornered a female lawmaker because he was angry with her and proceeded to harass her and block her from leaving the room.
Manning's report said staffers and lobbyists were also frequently the targets of Patterson's outrageous behavior and that many of them refused to be alone in a room with him.
At one point in the investigation, the report said, "we were told that a lobbyist stated that Rep. Patterson indicated that he would trade his vote on a bill for sex." However, the report did not detail who made the allegation or whether it was credible.
The report also said Patterson had admitted to staffers at the Capitol that he "frequently uses marijuana." But when questioned about it, he dodged.
"Tellingly, during our truncated interview with him, he refused to answer questions about his 'frequent use of marijuana' while steadfastly denying having ever used cocaine, methamphetamine, or any other illegal drug," the report said.
Manning and his team recommended that Patterson be kicked out of office as soon as possible. The House gave Patterson until April 10 to respond to the allegations.
Read the investigation: