Lawyers in the first federal trial challenging the constitutionality of California’s Proposition 8, which bans marriage equality in the state, submitted new written arguments on Friday to the judge who will decide the case, the Associated Press reports.

In the papers filed with Judge Vaughn Walker, only the lawyers arguing in support of the antigay law offered new twists to their argument that marriage equality could undermine heterosexual marriages.

As the AP reports: “The potential harms they cited included giving bisexuals a legal basis for pursuing group marriages and unmarried fathers incentive to abandon their children.”

Lawyers arguing against Prop. 8 say there is no evidence to back those claims.

Walker is set to schedule closing arguments in the case soon.