Frustrated by legislative inaction, the federal judge who found Minnesota's sex offender program unconstitutional has threatened a "more forceful solution" if state leaders fail to implement immediate reforms.

In a harshly worded order issued Wednesday, Judge Donovan Frank of the U.S. District Court in St. Paul called on the state to correct systemic problems with the Minnesota Sex Offender Program (MSOP), which locks up about 720 sex offenders who have completed their prison terms but are deemed unsafe for public release.

Frank gave the state until Sept. 21 to file proposals, and he scheduled a public hearing on the remedies for Sept. 30.

While Frank did not specifically say that he would order the release of sex offenders, his order suggested that events could force him to take dramatic action to protect the constitutional rights of those being held at the MSOP's secure treatment centers in Moose Lake and St. Peter. Critics have said the system amounts to unconstitutional indefinite detention.

"Any delay by the state to prepare for the inevitable relief to be imposed by the court in light of the previously determined constitutional violations would only increase the risk to public safety," Frank wrote.

Frank's latest order comes just days after he summoned Gov. Mark Dayton and more than a dozen legislators and other public officials for a closed-door meeting to attempt to reach a consensus on ways to bring the program up to constitutional standards.

The meeting was a failure: Although Dayton made several proposals, most of the legislators brought few ideas and they departed several hours later without agreeing on a course of action.

A spokesman for Dayton said Wednesday he is traveling on a trade mission to Mexico and will review the court's order with his commissioners and legislative leaders after he returns Saturday.

Dayton and state Attorney General Lori Swanson have said they intend to appeal Frank's June ruling declaring the program unconstitutional, which could delay reforms for at least another year.

"The overall tone [of Frank's order] indicates to me that the judge is growing impatient with the pace of the process, and expects the state to get moving," said Dan Gustafson, the lead attorney representing a class of sex offenders suing the state in the case. "It certainly suggests that Frank will take action … and the state better be prepared to do what he orders."

A court-ordered release of convicted criminals would not be unprecedented. In 2013, a federal court in California ordered the release of nearly 10,000 prison inmates after the state ignored the court's repeated calls to solve severe overcrowding.

In Wednesday's order, Frank signaled his frustration, noting that "insufficient funding is not a defense," and he laid out several specific measures that could be taken. These include entering into contracts to provide independent, periodic assessments of offenders to determine whether they still meet the criteria for confinement in the MSOP; the establishment of less-restrictive treatment options in the community, and designing a "statewide public education program" that would correct misinformation about the system for treating and releasing sex offenders.

"Recognizing the history of the state's failure to meet minimum constitutional requirements, as well as the continuing injury and harm resulting from these serious violations, the court notes that, at some point, if the state proves unwilling or incapable of remedying the constitutional violations, to which insufficient funding is not a defense, that failure may demand a more forceful solution," Frank wrote.

While 20 states civilly commit sex offenders, Minnesota is unusual in both the number of offenders it commits for treatment and the duration of their confinement. In the program's 20-year history, no offender has been unconditionally discharged from the MSOP, and only four have been provisionally discharged.

In a long, contentious trial early this year, MSOP administrators admitted they may be detaining untold numbers of offenders who no longer meet the state's legal requirement for confinement.

Chris Serres • 612-673-4308

Twitter: @chrisserres