Hoak was indicted on a charge of first-degree murder in the Feb. 9, 2003, shooting death of Larry G. Hose outside Images nightclub west of Charles Town.
The jury continued deliberating in the case Tuesday morning and into the afternoon after a lunch break.
Steptoe then called together attorneys in the case to relay to them a note he received from jurors.
The note said that although there had been some change in their position, they still were having trouble reaching a verdict.
Jurors then took back the note as if they had changed their minds about its contents, defense attorney Harley O. Wagner said. Jurors sent Steptoe another note at about 4:50 p.m.
In that note they said they had been "vigorously" deliberating all day, but that the process was "disintegrating" and they feared they would not be able to reach a consensus.
Steptoe sent back a note asking jurors if they were hopelessly deadlocked, to which they responded affirmatively.
Jefferson County Assistant Prosecuting Attorney Larry Crofford made a motion to declare a mistrial and Steptoe granted it.
After the jury was called back into the courtroom, Steptoe acknowledged its "extraordinary" attempt at trying to reach a verdict. Steptoe said pressing the matter further would be too much like "coercing a verdict, which would not be in the public interest."
Outside the courtroom after the decision, defense attorney Kevin D. Mills said Hoak and the defense team were extremely gratified by the careful consideration jurors gave to the case. Mills said there was "clear evidence" that Hoak was acting in self-defense when Hose, 29, of Kearneysville, W.Va., was shot once in the chest.
Hoak testified that Hose accused him of having an affair with Hose's ex-wife, Melissa Tanner, and that Hose began calling him on the telephone and threatening him.
Mills said in his opening statement that Hose threatened to shoot Hoak and that Hose tried to burn down Hoak's house by tossing a Molotov cocktail at it.
Hoak thanked the jury for its work on the case.
"I think they did a fair job. I thank them for that," Hoak said.
The trial started May 10 and lasted 10 days, the longest trial in recent memory in Jefferson County, according to attorneys in the case.
"It's a tough case. There are a lot of different theories," Crofford said Tuesday.
Members of Hose's family had been in the courtroom Tuesday but were not there when the mistrial was declared.
Because the charge of first-degree murder still stands against Hoak, prosecutors must decide whether they want to have another trial, discuss plea options with defense attorneys or dismiss the charge.
"I don't see that as being likely," Crofford said of a dismissal.
The attorneys are scheduled to appear before Steptoe on June 13 to determine how to proceed.
Wagner said Tuesday he talked to four jurors, who relayed to him how the group was split on possible verdicts.
Wagner said jurors told him the panel discounted returning a first-degree or second-degree murder verdict against Hoak within a few hours after deliberations began Friday.
The rest of the time, jurors struggled between a verdict of voluntary manslaughter and not guilty, Wagner said.
Late Friday, eight jurors favored a not-guilty verdict and four favored a voluntary manslaughter verdict, Wagner said. Monday, two jurors favored not guilty and 10 favored guilty of voluntary manslaughter, Wagner said.
On Tuesday, seven jurors favored not guilty and five favored guilty of voluntary manslaughter, Wagner said.
Hose was shot in the early hours of Feb. 9, 2003, outside Images nightclub.
Hoak testified during the trial that after he entered the bar, Hoak said he saw Hose, who motioned for Hoak to come over to him.
Hoak said there was a conversation during which Hose asked Hoak to stop calling the police and Hoak said he asked Hose to leave him alone.
Hoak said after a bouncer suggested to him to "let it go," he shook hands with Hose.
Hoak said he met up with Hose again outside the bar and asked Hose if everything was OK. Hose made a comment that indicated everything was not OK, Hoak testified.
Hoak broke down on the stand as he recounted the string of events and said he did not remember the gun going off.
Jefferson County Prosecuting Attorney Michael D. Thompson played down the self-defense argument.
Thompson called jurors' attention to a conversation the bouncer at Images had with Hoak after Hoak and Hose got into a heated discussion at the bar.
After the bouncer told Hoak that he should "let it go," Hoak responded with words to the effect that "he was going to end this tonight," Thompson said.