Legal trouble for New England Patriots owner Robert Kraft stemming from back-to-back visits to a Florida massage parlor last January appears to have gotten worse after prosecutors submitted a new court document last week.

The filing from the state Attorney General’s Office suggests the 78-year-old Kraft, who has owned the six-time Super Bowl champions since 1994, could face a third-degree felony charge -- and possibly five years behind bars -- if the state wins an appeal of a judge’s May ruling that tossed out all evidence collected against Kraft, including videos.

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That judge ruled that police lacked a “sneak and peek” warrant when they operated cameras non-stop for five days inside the Orchids of Asia Day Spa in Jupiter, which authorities say Kraft patronized last Jan. 19 and 20, according to the Sun Sentinel of South Florida.

Kraft, a part-time resident of Palm Beach, is accused of paying for sex acts at the business, the newspaper reported. While soliciting prostitution is normally a misdemeanor, Kraft’s new predicament appears to stem from allegedly having paid for sex “on multiple days,” according to the report.

The billionaire’s legal team had argued that police went to excessive lengths to crack down on what amounted to misdemeanor offenses – and violated Kraft’s Fourth Amendment right to protection from unlawful searches and seizures. But the state’s attorneys argued that police were investigating a broader scope of possible offenses that included the more serious charge of sex trafficking.

“The investigation at issue here culminated in numerous felony charges against the owner, manager, and employees of the Spa,” the state’s attorneys wrote Dec. 17, according to the Sun Sentinel. “In addition, any person who purchased prostitution services on multiple days, as Mr. Kraft did, committed a felony.”

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Nearly 300 men were charged last February in connection with the investigation, which examined operations at 10 Florida spas.

Lawyers for the state are seeking to make their case in person before the 4th District Court of Appeal in West Palm Beach.

The Sun Sentinel was unable to reach Kraft’s lawyers for comment.