BISMARCK (AP) — Court officials and lawyers in North Dakota say few people have tried to undo convictions for refusing DUI blood tests in the year since a state Supreme Court opinion offered a narrow pathway for doing so.

The North Dakota high court ruled in 2018 that a 2016 U.S. Supreme Court decision found it unconstitutional to criminalize refusal of a warrantless blood draw applies retroactively. The 2016 decision was based on cases in North Dakota and Minnesota involving alcohol testing.

The North Dakota justices said in their ruling that any post-conviction relief applies “in very limited circumstances” such as time of the conviction and the “legal landscape” as it existed at the time of each case. Even so, Bismarck attorney Dan Herbel, who argued in both the 2016 and 2018 cases, said it doesn’t appear many people are taking advantage of the state ruling.

“I don’t know if a lot of people are even aware that they have the option of vacating a prior conviction based upon these cases,” Herbel told The Bismarck Tribune.

The Minnesota Supreme Court in late 2018 also ruled that the U.S. Supreme Court case applies retroactively.

Attorney Jonathan Green, of Wahpeton, said he’s sent letters to people he can find who have convictions for refusing warrantless blood draws. He’s received phone calls from about a dozen people and has filed petitions for about half. Judges earlier this month vacated Burleigh County convictions for a Fargo woman and a Bismarck man for whom Green sought relief under the state Supreme Court ruling.

Aaron Birst, a former Cass County prosecutor and now executive director of the North Dakota State’s Attorneys’ Association, said prosecutors aren’t actively looking over cases in which the law might have or has changed, so anyone who believes his or her case should be revisited should contact a lawyer.