Authorities in Phoenix will be looking into the activities of Bishop Thomas O'Brien in the hours before Saturday's fatal hit-and-run accident.
Maricopa County Attorney Rick Romley said, while the length of time between the accident and O'Brien's arrest precluded standard sobriety tests, "There are some things that we can do."
He said investigators will question people who saw O'Brien earlier in the day, when he's said to have attended several confirmations.
O'Brien, 67, was booked Monday and subsequently released after posting $45,000 in bail, and declined to answer any questions as he passed reporters outside the jail.
At a press conference, Romley said O'Brien was charged with a class four felony for leaving the scene of a serious accident.
O'Brien's attorney, Jordan Green, declined to comment on the arrest.
O'Brien made headlines earlier this month when it was announced that he relinquished some of his authority in an unprecedented agreement with prosecutors that spared him from indictment on obstruction charges for protecting child-molesting priests.
In the hit-and-run case Saturday night, 43-year-old Jim Reed died after he was struck while walking across a street in the middle of the block about three miles from the bishop's home.
CBS News Correspondent Vince Gonzales reports the Bishop initially told police he was driving in the area after Saturday Night mass and may have hit something. Authorities say he never reported the incident, and once he learned that investigators were looking for his car, he apparently tried to have the damaged vehicle fixed.
Romley said contrary to early reports, it is not clear that a second car was involved in the accident. Because of the nature of the injuries, investigators believe that some time after the initial collision, a second car likely ran over the victim and dragged him.
Sgt. Randy Force, a police spokesman, said O'Brien has not being charged with causing the accident because the victim had been jaywalking.
"If the bishop had remained at the scene, in all likelihood he would not have been charged with any crime," Force said.
"Quite honestly, the charge of leaving the scene of a fatal accident is a very serious charge," Glenn Garrer, commander of the police traffic unit in Phoenix, told the CBS News Early Show. If convicted, O'Brien faces up to four years in jail. There will be a hearing in the case next week.
Police said in court documents that O'Brien told them he thought he had hit a dog or a cat or that someone had thrown a rock at his car.
Some officers doubted that explanation. Reed was six feet tall and weighed 235 pounds. "Obviously, something that large, it would be very difficult to hit it and not recognize that you had struck something," Garrer said.
Witnesses gave police a partial license plate number from the car, which led investigators to the diocese, Sgt. Laurie Williams said. The diocese told the police that it was O'Brien's car, she said.
Police went to the bishop's home with a search warrant and examined the car. The tan Buick's windshield was caved in on the passenger's side, Williams said. The warrant called for any evidence of blood, hair or glass samples, Williams said.
The court documents say that O'Brien had driven the car to Mass on Sunday and to visit his sister in Scottsdale. He had also made a call about having the windshield fixed, police said.
The documents said a priest had informed O'Brien on Sunday night that police were looking for him but that the bishop never contacted authorities.
O'Brien was hospitalized briefly after his arrest, complaining of high blood pressure problems. Garrer said O'Brien's attorney had advised the bishop against answering further questions.
In a statement, Monsignor Richard Moyer, the diocese's chief of staff, said the diocese would cooperate with the investigation.
"I sincerely regret reports I have received about Bishop O'Brien being involved in a fatal accident," Moyer said. "The sympathy of all of us in the Diocese of Phoenix as well as our prayerful support goes out to the victim's family."
The Arizona Republic reports that some church insiders believe O'Brien will resign or retire within days.
Monsignor Francis Maniscalco, spokesman for the U.S. Conference of Catholic Bishops, declined to comment on O'Brien's arrest.
Some U.S. Catholic bishops have previously been arrested during political protests. And in 1985, the former president of the U.S. Conference of Catholic Bishops, Archbishop John R. Roach of St. Paul and Minneapolis, pleaded guilty to drunk driving and was sentenced to 38 hours in jail, a fine of $445 and ongoing substance abuse treatment. He did not resign as archbishop over the incident and served another decade.
O'Brien has been a priest since 1961 and spent his entire career in Arizona. He has served in Phoenix since 1964, starting as a parish priest and quickly climbing the ladder of diocesan leadership. O'Brien has been the spiritual leader of 430,000 Catholics in Arizona since 1981.
In the agreement with prosecutors announced earlier this month, O'Brien admitted that he allowed priests to work with minors after he knew of sexual misconduct allegations against them and that he transferred them to ministries without telling their new supervisors.
Under the deal, O'Brien agreed among other things to appoint the church equivalent of a chief of staff to supervise the enforcement of the church's sexual misconduct policies.