CHESTER COUNTY — The grandson of a slain woman in Chester County had been scheming since before Christmas in a $5,000 murder-for-hire plot involving a high school friend and another man because the grandparents he lived with were too strict, police announced Friday.

Jimmie Diane Paul, 59, was shot three times after she came home Tuesday after 6 p.m., said Maj. Bill Murphy of the Chester County Sheriff’s Office. However, Mack Paul, her husband, never came in the house after arriving first. Jimmie Paul was shot three times upon entering the home, Murphy said.

The guns used in the crime, including the murder weapon, came from the Paul home and were given to the other two defendants by the grandson, Murphy said.

The scheme was hatched by Clayton Eli Watts, 17, to kill the grandparents he lived with before Christmas but did not happen until Tuesday, Murphy said. Watts contacted a friend at school, Marquaes Issale Eric Buchanan, 18, Murphy said, and then Buchanan enlisted the help of a third man, Shaiderius Demarck Cohen, 19, who was arrested late Thursday.

Cohen is believed to have been the shooter, Murphy said.

“The plan was to pay them $5,000 to kill both,” Murphy said. “This scheme had been orchestrated. He wanted to kill both his grandparents.”

However, no money changed hands, Murphy said.

The plot remained hidden for a month while Watts still lived with his grandparents, Murphy said.

Watts, who had lived with his grandparents for some time, had been asked by his grandparents to clean his room, do his schoolwork and homework, be home at a decent hour and abide by the rules of the home, said Murphy.

"They asked him to do what any decent parent does, basic rules," Murphy said. "There doesn't appear to be anything that they asked him to do that other parents don't ask of their children."

Watts also had his own car - the same one he used to pick up the other two defendants Tuesday, Murphy said.

Neither Watts not Buchanan has a criminal record, Murphy said. However, Cohen was arrested by Chester City Police officers for trespassing on Jan. 8, yet gave police an alias when charged, Murphy said.

After picking up Buchanan and Cohen on Tuesday, Watts gave them the two handguns, Murphy said. The three then lay in wait at the home at 1313 Williamsville Church Road for both Jimmie Paul and Mack Paul to return home from work.

Mack Paul is the Chester County Planning Director, and Jimmie Paul was an employee in the Chester County Clerk of Court Office.

One of the weapons has been recovered.

Police continue to interview other people, including peers at Chester High School where both Watts and Buchanan went to school, Murphy said. A list of graduates furnished by Chester High in 2012 included Cohen.

Other charges may be pending, Murphy said, as the investigation continues.

All three suspects are being held without bond on murder and weapons charges in the Chester County jail, and could face punishment up to the death penalty if convicted

Bond in murder cases can only be set by a circuit court judge. Chester County does not have criminal court again until Feb. 24, said Doug Barfield, 6th Circuit Solicitor. Citing the ongoing investigation, Barfield declined to discuss the case other than he has been in contact with police since the night of the shooting.

All three defendants were set to be screened for lawyers Friday - all criminal defendants if indigent have a legal right to a court-appointed lawyer. The public defender office likely will have one of the defendants, while private lawyers who are on the appointment list for Chester County will handle the other two, said Mike Lifsey, 6th Circuit Chief Public Defender.

Lifsey declined further comment on the case, saying he had not yet received any materials from law enforcement on the case.

Arrest warrants allege both Watts and Buchanan admitted the crime. Cohen had not made a statement to police, said Murphy the deputy.