LOCKPORT — A defense attorney put himself on the Niagara County Court witness stand Friday in an effort to prove that his client had hired him in time to make incriminating statements inadmissible in an upcoming trial over the death of his baby daughter.

E. Earl Key placed his own cell phone records into evidence in an effort to help Nicholas A. Doxey, 23, avoid the impact of spontaneous statements made to a detective by his girlfriend Sara E. Nigro, 23.

Their second child, Sierra Marie Doxey, died March 4, 2008, from a morphine overdose that occurred in the apartment the couple then shared on Garden Street. However, they didn’t learn of the toxicology results until March 25, 2008; before that, they had been telling people the girl died of pneumonia.

When Lockport Detective Lt. Scott Seekins told them of the results, according to earlier testimony, Nigro said to Doxey, “I can’t believe you did this. . . . You were supposed to be watching her.”

Those statements, which Judge Matthew J. Murphy III has ruled admissible, also caused him to order separate trials for the couple, both of whom are charged with criminally negligent homicide.

Key was questioned Friday by Nigro’s lawyer, Michele G. Bergevin, and by Samuel Davis, a Buffalo attorney helping him with the case.

Key said his cell phone records and recollections indicate that Doxey called him to complain about Seekins’ questioning as early as March 4 and that Key himself called Seekins on March 11 and left him a message that he represented both suspects.

Doxey took the stand to say that police kept coming to the apartment and he refused to let them in. Key said that was his advice, and the woman who raised Doxey from age 4, Loretta Kolek, testified she told Doxey the same thing.

Doxey testified that he was then out on bail while appealing a drunken driving conviction, but it was Nigro who let Seekins into the apartment March 25. “I felt if I didn’t speak to him, I’d go back to jail,” Doxey said.

Kolek said she called police March 24 and told them Doxey and Nigro wouldn’t talk unless she and a lawyer were present.

Key then put the prosecutor on the witness stand.

Assistant District Attorney Claudette S. Caldwell testified that she didn’t learn Key was involved in the case until early April 2008, and she said Key’s name wasn’t mentioned in any of the Lockport police notes and reports she has. She said Key’s name came up “only verbally.”

Key said he wants to recall Seekins and Detective Capt. Richard L. Podgers to the witness stand; Judge Matthew J. Murphy III scheduled that for Dec. 4.

Murphy also said he might reconsider his ruling on separate trials, saying another possibility is one trial with two juries. That will also be discussed at the Dec. 4 session.

In another dead-baby case, Murphy asked Bergevin to make a written argument seeking dismissal of an indictment against Air Force reservist Jason K. Kirchner, 27, of the Town of Niagara.

He is charged with manslaughter and criminally negligent homicide in connection with the May 21 death of his 7- month-old daughter from a head injury.

The death of Abbigail V. Kirchner originally was ruled accidental, but a grand jury returned an indictment in late September after Caldwell presented evidence. Murphy is considering whether the evidence was legally sufficient to support the charges. Kirchner will return to court Dec. 22.