Federal prosecutors handling a large-scale marijuana distribution case, one tied to the disappearance of Amos Mortier from his Fitchburg home four years ago, have asked two defendants to tell them where they were when Mortier vanished.

But attorneys for Brent Delzer and Jacob Stadfeld said Thursday that because their clients aren't charged with anything having to do with Mortier's absence, their whereabouts is irrelevant.

Prosecutors have never said openly how closely tied the conspiracy is to the disappearance of Mortier, 27, who was last seen on Nov. 8, 2004. Instead, there have only been hints at the ties between the drug case and Mortier's disappearance, found in scattered court documents related to other defendants tied to the case.

One of those documents makes a passing reference to "the murder of Amos Mortier."

Unlike the other defendants in the drug case, who are being prosecuted under charge-and-plea deals tied to cooperation with investigators, Delzer, 35, and Stadfeld, 32, both of the Madison area, were indicted by a grand jury for allegedly taking part in a conspiracy to distribute hundreds of pounds of marijuana that had been brought to Wisconsin from Canada through East Coast distributors.

Delzer and Stadfeld were charged with being part of the conspiracy from about 2000 to Nov. 8, 2004 — the day Mortier was last seen.

On Nov. 20, Assistant U.S. Attorney Dan Graber requested a notice of alibi from Delzer and Stadfeld, asking for the "specific time and place where each defendant claims to have been" on Nov. 8, 2004, between noon and 5 p.m. He also asked for the name, address and phone number of each person on whom the alibis are based.

Graber could not be reached for comment Thursday.

Delzer's attorney, Jeff Nichols, responded in court papers Thursday that Mortier is not named as a co-conspirator in the indictment, and the indictment doesn't allege that either Delzer or Stadfeld was involved in Mortier's disappearance.

"Absent some allegation of specific wrongdoing by the defendants on Nov. 8, 2004, to further the alleged conspiracy, a notice of alibi for that date is not relevant," Nichols wrote.

He said prosecutors have not alleged anything more specific about that date other than that is the date the drug conspiracy is alleged to have ended. And without a bill of particulars from the government, Nichols wrote, his client "cannot know specifically what criminal activity he is alleged to have engaged in on that date."

Stadfeld's attorney, Ernesto Chavez, said he plans to join Nichols in opposing the government's alibi request.

"There's no evidence my client took part in that," Chavez said. "There's no evidence they even know it's a homicide. It's a little tricky. We think there are other reasons."

Chavez and Nichols will also file motions to dismiss the indictments against their clients, citing non-prosecution agreements that prosecutors have with the men. Prosecutors maintain that Delzer and Stadfeld breached those agreements.

The defense attorneys also want to push back a hearing on the issue set for later this month because they need more time to prepare.