Assistant U.S. Attorney Paul Gray said in a court filing last week that Sigel had "utterly failed to cooperate" with a probation officer's attempts to determine his financial condition.
He said that the lack of cooperation showed Sigel's "continuing disrespect" for the legal process.
Gray said that the government had "expressly agreed" to several continuances of Sigel's sentencing so that he could "earn money and, at the very least, make a start on paying restitution to the IRS."
Gray contends that Sigel paid a "paltry" $10,000 in taxes between 1999 and 2005, and owes more than $728,000 for those years. (Defense attorney Fortunato Perri Jr. said at Sigel's plea hearing that he owes less than $300,000 in back taxes.)
The prosecutor said that Sigel has failed to file income-tax returns for more than a decade.
Gray said that Sigel would not permit his probation officer to visit him at home, which he called "a most basic part" of pre-sentence procedure.
Perri said Wednesday that the defense would address government concerns at sentencing.
Sigel is no stranger to the criminal-justice system.
He served 10 months in prison in 2005 for illegal gun possession, and in 2008 he was sentenced to serve a day in jail and six months in a halfway house for violating his probation on that charge.
He also beat an attempted-murder charge stemming from a shooting in West Philadelphia.
Contact Michael Hinkelman at 215-854-2656 or firstname.lastname@example.org, or follow on Twitter @MHinkelman.