MORTON - A physician accused of the mercy killing of her autistic 3-year-old daughter is on suicide watch in the Tazewell County Jail.

Dr. Karen McCarron, a 1995 graduate of Southern Illinois University School of Medicine in Springfield, is charged with first-degree murder in the death of her daughter, Katherine "Katie" McCarron

Katie was smothered with a white plastic garbage bag May 13. Her mother could face 20 to 60 years in prison if convicted.

Ron Hamm, one of two attorneys for McCarron, has said he wants her bond to be reduced. He plans to argue in court today that, because she has no criminal history and poses no flight risk, McCarron would comply with reasonable conditions and should be released.

McCarron reportedly told police that her eldest daughter's autism had regressed and she refused to take a nap. McCarron told her mother, who was visiting the McCarron home in Morton, about 10 miles southeast of Peoria, that she was going to take the toddler for a drive, which she frequently did to calm the girl down, authorities said.

Instead, investigators believe, McCarron took Katie to her mother's house and suffocated her.

McCarron, 37, said she wanted to "end her pain and Katie's pain," according to a Tazewell County court record.

Police received a 911 call May 13 that the toddler was not breathing and her mother was doing CPR. Katie was pronounced dead at OSF Saint Francis Medical Center in Peoria.

Emergency crews were called again the following day, Mother's Day, after McCarron reportedly tried to overdose on over-the-counter pills. Police found McCar-ron and her husband, Paul, hugging and him crying. McCarron had just told him she had killed their daughter, police said.

Paul McCarron, an engineer for Caterpillar, had just returned from a business trip in North Carolina. The McCarrons' other daughter, Emily, 2, is with her father.

A friend of Karen McCarron told Peoria Journal Star columnist Phil Luciano that McCarron had become increasingly upset when her daughter's condition worsened after the family took her to North Carolina for treatment. The friend, who did not want to be named, also said McCarron had been taking anti-depressants.

McCarron is certified in anatomic and clinical pathology as well as dermatopathology, the study of the causes and nature of skin diseases.