Los Angeles ? Robert Blake was afraid his wife-to-be would expose their child to a life of drugs and crime — so he plotted a year before her murder to gain custody, a private investigator testified.

William Jordan said Friday he was trying to get Bonny Lee Bakley to leave her infant daughter in California in a plan hatched with Blake four years ago.

“He didn’t think Bonny was a good mother for Rosie,” Jordan said Friday. “He wanted the baby. … It was constantly on his mind, I think.”

Blake, 70, is charged with killing 44-year-old Bakley on May, 4, 2001. The couple married just months before Bakley was killed. He has pleaded not guilty.

Bakley was found shot to death in their car outside a restaurant where they had dined. Blake told police he found his wife mortally wounded after he went back to the restaurant to retrieve a handgun he carried for protection.

Jordan testified that a similar scene had played out before — he dined at the same restaurant with Blake as many as seven times and the former “Baretta” TV star went back during one of those visits to retrieve a gun he said he’d forgotten.

Jordan took the witness stand for two hours during a “conditional examination” to be played for a jury if he is unable to testify at trial. Prosecutors, however, said the 78-year-old retired Los Angeles policeman likely would be available for the trial scheduled to begin Nov. 1.

Jordan said he was hired by Blake in the summer of 2000 and worked three or four months for him in anticipation of custody proceedings over Blake’s daughter, who was born in June of that year.

The investigator said he developed a plan in which Bakley, who lived in Little Rock, Ark., met with Blake in California.

At the meeting, Jordan warned that she could be arrested for traveling so far from home under conditions of her parole for a conviction involving false identification.

Blake persuaded Bakley to leave Rosie with him, Jordan said.

But, he testified, Bakley’s arrest had been unlikely.

“I considered the whole thing a gimmick to get her to give him the baby,” Jordan said.

Blake told the investigator he was concerned that if Bakley was permitted to raise the girl, Rosie “would be exposed to the wrong elements, including drugs, prostitution and things of that nature,” Jordan said.

Blake is free on $1.5 million bail but remains under house arrest. He is due back in court for an evidentiary hearing Sept. 17.