Do it during the day, get as close as you can and watch out for the baby.

That was just some of the advice that prosecutors say Brian Mayhew gave associates in a series of jailhouse phone calls that allegedly show he ordered the execution of his uncle Nicoh Mayhew, 26, from a Prince George’s detention center to cover up his role in the slaying of two other men.

Prosecutors played the calls in public for the first time Tuesday in Prince George’s County Circuit Court, hoping the recordings and other evidence will be allowed in the trials of Brian Mayhew and Kenan Myers. Judge Larnzell Martin Jr. ruled that he would allow the the calls to be heard during the trial, scheduled to begin Jan. 27.

Mayhew and Myers are facing first-degree murder charges in the 2011 shooting deaths of Sean Ellis, 24, and Anthony McKelvin, 28. Mayhew’s uncle, who was scheduled to testify against him and Myers in connection with the slayings, was shot in the head while carrying his 2-year-old son in December 2012, just months before the start of that trial.

If a jury can be convinced that Brian Mayhew, 22, went to such lengths to have an uncle killed to prevent his testimony, it could reinforce the allegation that Mayhew was trying to hide his guilt in the deaths of Ellis and McKelvin, prosecutors believe.

During Tuesday’s hearing, Brian Mayhew’s then-girlfriend, Asha Smythe, walked the court through the calls. Smythe said she set up three-way phone calls so that Brian Mayhew could communicate with his associates while he was in jail.

In the calls, the voice that prosecutors say is Brian Mayhew’s talks about having to do something in the daylight and that “9 to 11” “would be a good time.” He then gives directions on how to get to a location, saying that it’s “just one flight” of stairs and that “it’s going to be on your back wall and to your right.” Prosecutors argue the directions were to an apartment that Nicoh Mayhew would be heading to.

The voices on the line also talk about how a baby might get in the way, with the voice identified as Brian Mayhew’s saying later that if he were going to do something he would get as close as he could.

The voice that Smythe identified as Brian Mayhew’s also tells the other person on the line that someone would be showing up with “the white girl named Kia” the night before “showtime.”

Nicoh Mayhew was expected to be driving his girlfriend’s white Kia on the day of his killing, which occurred at 9:54 a.m.

In a call later that day, one of the alleged gunmen reported back to Brian Mayhew. “Your man lost his mind,” the voice on the line said. “He was going crazy.”

The calls played Tuesday span from Nov. 28, 2012, to Dec. 19, 2012, the day Nicoh Mayhew was killed

During the hearing, Martin asked whether the phone calls would distract jurors, drawing their attention away from the deaths of Ellis and McKelvin by focusing on the killing of Nicoh Mayhew instead.

John M. McKenna, the attorney for Brian Mayhew, tried to shake Smythe’s credibility as a witness, pointing out that she has worked out a plea deal with state prosecutors. McKenna said Smythe could have faced the death penalty or life in prison if convicted of taking part in a conspiracy to kill Nicoh Mayhew. Smythe testified that she expects to serve 13 months and to be released in April.

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