Prosecutors said Monday they intend to seek a 21-month sentence for Boucher.
Paul was treated previous year for several broken ribs and pneumonia as a result of the attack.
Paul said neighbor Rene Boucher attacked him in November while he was mowing his lawn and wearing headphones.
Boucher has been charged with assaulting a member of Congress as part of a federal plea agreement that surfaced last Friday.
The Justice Department said Boucher has signed a plea agreement at the federal level, though date has been set for the official taking of his guilty plea and sentencing.
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The two later engaged in a long rally that consisted of 31 shots, with Sandgren finding the net to bring the game to deuce. Kerber has been the only Grand Slam singles champion in the women's draw since her third-round win over Maria Sharapova.
Boucher faces possible prison time, and his attorney says he is "very regretful" about the attack and that it had to do with the upkeep of their yards.
"Everyone needs to remember, first and foremost, that this is a dispute between two neighbors", Baker said in a phone interview.
The document, posted Monday, also makes clear that the attack was not politically motivated.
Paul can be heard laboriously breathing, saying he had been attacked by a neighbor and requesting police presence. You can listen to it in the video below, via NBC.
Paul did not see Boucher coming until the last second and was "unable to brace for the impact", the plea document said. The Kentucky senator received six broken ribs and developed pneumonia from the incident, and has described the injuries as a "living hell". He described the incident-which left him with five broken ribs-as "not a life-or-death thing", but said he would "like to have a police auto come by". Boucher admitted tackling Paul but denied that attack had anything to do with politics. He has pleaded not guilty to that charge. The case was investigated by the FBI's Louisville office. He could face as many as 10 years in prison and a fine of up to $250,000.