The attorney general’s office says it told Mr. Abelove that it was reviewing the case — which meant that he was not to take any significant action. He instead moved recklessly ahead, inflicting just the kind of damage the executive order was intended to prevent. According to court documents, he hurriedly took the case to a grand jury only five days after the shooting. The jury then failed to indict the officer.

Last week, New York’s attorney general, Eric Schneiderman, sued Mr. Abelove, asking the court to remove him from the case. Mr. Schneiderman argues, and rightly so, that the grand jury was invalid because Mr. Abelove lacked legal jurisdiction over the case.

The Albany Times Union has raised questions about the competency of Mr. Abelove’s prosecution, reporting that two people who witnessed the episode had not been called to testify. Mr. Thevenin’s wife, meanwhile, has questioned the police’s account of what happened. She says the police initially told her that her husband had died in a traffic accident. The police have said that the officer fired after Mr. Thevenin moved his vehicle, pinning the officer against the bumper of another car.

The governor’s executive order gives the attorney general the right to intervene “where, in his opinion, there is a significant question as to whether the civilian was armed and dangerous at the time of his or her death.” The order specifically requires that a district attorney obtain state authorizations before making grand jury presentations in cases where civilians were “unarmed” or where there is a question about whether the person was armed or dangerous.