DANNY ROBBINS,Associated Press KAUFMAN, Texas (AP) — A tip pointing to a cache of guns and a vehicle hidden at a storage unit helped investigators to unravel a meticulous revenge plot that had culminated in the killings of three people, including two North Texas prosecutors, a sheriff said. Former justice of the peace, Eric Lyle Williams, and his wife, Kim Williams, are charged with capital murder in the fatal shootings of District Attorney Mike McLelland and his wife, Cynthia, and assistant prosecutor Mark Hasse. Investigators say the prosecutors had been concerned that William might be a threat to them after they successfully prosecuted him for theft last year, even going to the extent of carrying handguns following Williams’ conviction. Williams was sentenced to two years’ probation, lost his law license and his elected position as justice of the peace — a judge who handles mostly administrative duties. Hasse was shot by a masked gunman in January as he made his way to his courthouse office. The McLellands were gunned down two months later at their rural home. Sheriff David Byrnes told reporters Thursday that while Williams “has always been on the radar” — investigators questioned him after Hasse’s slaying and again after the McLellands’ deaths — authorities did not have the evidence to tie everything together until they found the storage unit. Authorities say a friend of Williams’ told them about the weapons. “The discovery of the storage locker probably was the watershed event that put us on to this,” Byrnes said. Authorities allege Eric Williams, 46, was the gunman in all of the slayings. They say his wife, who is also 46, was the getaway driver when her husband shot Hasse. They contend she was a passenger when her husband drove to the McLellands’ home to carry out those killings early on the morning of March 30. “Basically, this was a collaborative effort between Eric Williams and his wife,” Byrnes said. Eric Williams is being held on $23 million bail, and his wife is being held on $3 million bail. Online jail records do not indicate attorneys representing the couple. Criminal defense attorneys Toby Shook and Bill Wirskey, both former Dallas County prosecutors, have been appointed as special prosecutors. According to an arrest warrant, a friend of Williams’ contacted authorities last week and told them the former justice of the peace had told him he needed to rent a storage unit to hide some items because of his ongoing legal problems. Investigators searched the unit in Seagoville on Saturday and found a Crown Victoria matching security video of a car in the McLellands’ neighborhood the day they were killed, according to the warrant. Williams used a false name to purchase the Crown Victoria in February, the affidavit said. They also found guns, including eight .223-caliber weapons, authorities said. Investigators believe a .223-caliber firearm was used in the killings of the McLellands. Ammunition consistent with that used both in Hasse’s and the McLellands’ slayings was also found in the storage locker, according to the warrant. Investigators also traced emails to a computer in Williams’ home in which the author confessed to all three slayings and threatened more violence against county officials, the warrant says. Williams was arrested Saturday and charged with making a terroristic threat in connection with that email. Kim Williams was arrested Wednesday. An arrest affidavit contends she confessed to the killings and told investigators her husband was the gunman. Williams was elected to his judicial post in 2010 after practicing law in the county east of Dallas for a decade. He previously served as a peace officer in five North Texas cities and two counties, including Kaufman, according to records obtained by The Associated Press from the Texas Commission on Law Enforcement Officer Standards and Education. As recently as December 2010, he was a reserve officer in the Kaufman County Sheriff’s Department. During his theft trial, McLelland and Hasse portrayed Williams as a dishonest public official with a dangerous streak. The prosecutors presented evidence during closing arguments indicating Williams had made death threats against another local attorney and a former girlfriend. Williams has appealed the conviction, and on March 29 — a day before the McLellands’ bodies were found — a state appeals court in Dallas agreed to hear oral arguments in the case. Marcus Busch, a U.S. Justice Department attorney who worked with Hasse in the Dallas district attorney’s office and later went into private practice with him, said he was stunned by the arrests. “I just don’t understand how somebody in a white-collar case who received probation decides to throw away his own life with the senseless murder of people who were simply doing their jobs,” Busch said.