Marquette, Mich. ? A woman charged with conspiring to bilk actor John Stamos of hundreds of thousands of dollars had a brief romantic fling with him when she was a 17-year-old high school student during a spring break trip to Florida in 2004, an attorney said Monday.

Defense lawyer Sarah Henderson made the allegation during opening arguments in the U.S. District Court trial of Allison Coss and Scott Sippola, even though the presiding judge last week ruled that testimony about whether the “ER” and “Full House” star had an intimate relationship with Coss would not be allowed. Opening statements are not testimony and cannot be considered by jurors as evidence but allow attorneys to outline the case they will present.

Stamos’ attorney, William Sobel, issued a statement through publicist Matt Polk that said: “The allegations made today in the courtroom by the defendants’ attorneys during opening statements will not be proven because they are simply untrue.”