"We are coming toward the end game of the dismissals, if you will," he said.
Also Friday, Gill's office filed notices of possible impeachment evidence in 48 other cases related to the narcotics unit.
Prosecution will move forward in those cases, according to a news release issued by the DA, but the notices alert judges and defense attorneys that there may be evidence that calls into question the credibility of a witness or witnesses. Similar notices are expected to be filed in another 25 cases in coming days.
Despite the problems with the 48 cases, Gill said there is additional evidence or witnesses beyond the Neighborhood Narcotics Unit that will allow them to be prosecuted.
"These are cases that we can fight and can litigate and that we need to fight and litigate to move prosecution forward," he said.
Controversy over the West Valley City narcotics squad erupted in March, when Gill announced that he would file to dismiss more than a dozen criminal cases, mostly involving drugs, due to unspecified issues with a narcotics detective whom he did not identify.
That officer turned out to be Shaun Cowley, one of two detectives who shot at and killed 21-year-old Danielle Willard in her car on Nov. 2. Cowley and his fellow officer, Kevin Salmon, alleged that Willard had just purchased drugs and was attempting to hit them with her car when they shot her.
Gill's office is reviewing the shooting to determine whether the use of deadly force was warranted.
On April 4, Cowley's attorneys said the city wanted to fire their client, based on allegations of mishandling evidence, insubordination, and dereliction of duty. A week later, the city announced that an internal audit of the narcotics squad revealed a number of issues, including failure to account for seized items, officers keeping "trophies" from busts and improper use of confidential informants. Money and drugs from narcotics cases may also be missing, authorities said.
Cowley and Salmon were subsequently placed on paid administrative leave. On April 17, the city announced it was placing another seven officers from the squad on leave.
The entire department is also under investigation by the FBI for Willard's shooting and allegations of corruption within the narcotics squad.
Gill said that after reviewing the 400 active cases, his office will begin sorting through adjudicated cases filed in the last three years involving the Neighborhood Narcotics Unit. That review will determine whether those cases can still be defended, or whether the defendants' convictions should be overturned. Gill said he was unsure how many such cases will be reviewed, but said the number will be larger than the 400 active cases.
Gill emphasized Friday that the dismissals are focused around "one or some" officers at the West Valley police department, and should not reflect on the agency as a whole.
"It would be unfair to have the conduct of one or some officers taint the integrity of the other good men and women [in the police agency,]" he said.
West Valley City manager Wayne Pyle said Friday that he and other officials trust Gill's judgment and were glad to hear that the review of criminal cases that could be dismissed is nearing an end.
"We have been in close cooperation and contact with [Gill] and appreciate the work he's doing," Pyle said. "We're happy to get through this and be moving on and improving our own processes and departmental efforts."