The direct move that former Minnesota House Speaker Paul Thissen is about to make from the Legislature to the Minnesota Supreme Court may be unprecedented in state history. While 17 former legislators have served on the high court since its 1849 establishment in territorial Minnesota, none appear to have left the Legislature and joined the high court in the same year, according to the governor’s office.

That circumstance is bound to lead some to believe partisan favoritism motivated DFL Gov. Mark Dayton’s sixth Supreme Court appointment. Thissen got Dayton’s nod Tuesday to succeed Associate Justice David Stras, who left to serve on the Eighth U.S. Circuit Court of Appeals.

Before crying “cronyism,” Minnesotans should know the résumé of Thissen the lawyer as well as Thissen the legislator. The Minneapolis DFLer is among the most accomplished attorneys to have served in the Legislature in the modern era. A graduate of Harvard and the University of Chicago Law School, Thissen clerked for a member of the Eighth U.S. Circuit Court of Appeals and served as an appellate-level public defender before entering private practice. He was a shareholder at the Twin Cities firm Briggs and Morgan before joining Ballard Spahr (formerly Lindquist & Vennum) in Minneapolis. He is senior counsel of its Health Law Group, providing legal services to health care providers.

Thissen’s legislative career has also been distinguished. He served 16 years in the House and spent six of them as the leader of the DFL caucus, either as speaker or minority leader. But his two bids for governor fell short; he ended his most recent reach for the governorship this year shortly after coming in sixth in a precinct caucus straw poll. He had already announced that he would not seek re-election.

On Tuesday, Thissen declared himself “ready to move from policymaking to principled interpretation of the law.” That interpretive work is bound to be seen as bearing Dayton’s stamp. When Thissen joins the bench — perhaps as early as next week — five of the high court’s seven justices will be Dayton appointees. Given Thissen’s age — he’s 51 — and the court’s age-70 retirement rule, Dayton’s mark on the court could last for many years. It’s to his credit, and Minnesota’s benefit, that this governor has taken his judicial appointive responsibility very seriously.