UPPER MARLBORO, Md. (AP) — A District of Columbia police officer embroiled in a paternity suit fatally shot his mistress before leaving their infant child to die in an overheated car, prosecutors said as the officer’s murder trial opened Monday.

Richmond Phillips committed the crimes because he was facing a paternity lawsuit and didn’t want to pay child support for a baby girl he fathered out of wedlock, prosecutor Angela Alsobrooks told the jury in her opening statement. A defense lawyer countered that his client “didn’t do this thing” and there wasn’t evidence for a conviction.

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Phillips was arrested in June 2011 after police located the bodies of 20-year-old Wynetta Wright and her daughter, Jaylin, in a park outside Washington. Prosecutors say Phillips shot Wright and then drove the child — still strapped in the car seat of her mother’s car with the doors closed and the windows up — a short distance away, leaving her to die in stifling heat. The girl was just days shy of her first birthday.

When Phillips invited Wright to meet him at the park to try to work things out ahead of a scheduled court date, one of only two things was going to happen, Alsobrooks told the jury.

“He was either going to talk her out of that paternity suit or he was going to kill her,” said Alsobrooks, the state’s attorney in Prince George’s County, Md.

Phillips is charged with first-degree murder, punishable by life in prison if convicted, along with other crimes. Surveillance video and phone records connect Phillips to the park where the killing occurred, DNA evidence links him to the murder, and he lied to investigators about his relationship with Wright, prosecutors say.

But defense lawyer Brian Denton said his client was innocent and that the case hinged on circumstantial evidence.

He said that although prosecutors have surveillance footage showing Phillips and Wright talking at Oxon Run Stream Valley Park, the video does not capture the moment when Wright was killed. He said the DNA evidence was unreliable and that many people, not just his client and Wright, would have had access to a park where cigarette butts, alcohol bottles and condoms are commonly found.

“They’re suggesting that no one else would have been in that park on a warm summer night,” Denton said of the authorities.

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Phillips met Wright at a nightclub while off-duty and their relationship soon turned sexual. But Phillips, who was already married with another child, ended contact with her after learning that she was pregnant, the jury heard.  Wright served Phillips with a paternity suit early in 2011 and a subsequent test confirmed that he was the father of her child.

The two got back in touch as Phillips faced the prospect of a paternity test. He invited Wright to meet her at the park on the eve of a scheduled court date in their paternity case, and Wright was excited to bring Jaylin so that she could see her father, Alsobrooks said.

The two spoke for hours, but the encounter turned deadly when Phillips shot Wright and moved her vehicle with the child still inside. A heat advisory was in effect at the time, and temperatures inside the car reached 125 degrees, Alsobrooks added.

“He allowed her to essentially cook in that car, hoping and praying that she would never be found,” said the prosecutor, referring to Phillips as a “deceptive, double-sided man.”

The first witness, Wright’s cousin, Donna Leggett, testified that she had helped Wright with the baby’s care and that she suggested that Wright approach Phillips about providing his share of financial support.

“I told her she (needed) to stop stressing and take the father up for child support,” she said.

The courtroom in Prince George’s County Circuit Court was crowded with Wright’s family and supporters, many of whom dabbed their eyes and wept quietly.

Phillips, who was assigned to a vice squad, has been suspended without pay pending the outcome of the case, police said.

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