SALEM – A Lynn couple who admitted running a prostitution ring and conspired to have a juvenile take the rap on a drug case will spend up to 10 years in prison.Richard E. Jones, 45, of 39A Cottage St., and Rhonda L. Adjutant, 33, of 87 Chestnut St., were scheduled to go on trial Monday in Salem Superior Court, but instead changed their minds and pleaded guilty to witness intimidation, attempted perjury and sharing earnings from prostitution.Jones was sentenced to serve 8 to 10 years in prison and Adjutant received 7 to 10 years in Framingham State Prison for Women on the intimidation of a witness charge against them.They also were given 3-to-5-year sentences on the remaining charges, but those will be served simultaneously with the primary term of incarceration, instead of one after another.As he handed down their punishment, Judge Howard J. Whitehead pointed out how the couple had “undermined the justice system” as they attempted to have a juvenile take the rap for Jones on a drug case. Whitehead noted the seriousness of having a juvenile go to jail, especially for a crime he was not involved in.Assistant District Attorney Michael P. Hickey told Whitehead that the case began in the summer of 2006 when police were focused on Jones. State police initiated wiretaps from May through August 2006 as part of their investigation into a prostitution ring and alleged narcotics ring.On Aug. 24, police executed a search of Jones’ Cottage Street home and found a .38 caliber revolver, just over 28 grams of crack cocaine, 22 grams of marijuana, along with a scale and drug related items.Jones was arrested and held in custody at the Middleton Jail.In the meantime, Adjutant, his girlfriend and mother of his 18-month-old daughter, had been just released from prison and was on parole, was in telephone contact with Jones at the Middleton Jail, but what they did not realize was that they were being intercepted and taped by local officials.Typically, all calls at the jail are screened.From Sept. 5 through Sept. 12, at least four calls were made between the couple in which they discussed having a 16-year-old Charlestown juvenile, known to them, take the fall for Jones on the drug trafficking case and in exchange he would receive compensation while serving his punishment in the department of youth services and when he gets out he would have pocket change.Adjutant brought the juvenile to a Boston lawyer, without the permission of his mother, to sign a one-page statement taking responsibility that the cocaine was his and he had left it in a bedroom bureau at Cottage Street.Jones had offered in his conversations with Adjutant to give anyone who took the case his green car, Hickey said.The couple also ran a prostitution ring from July 15, 2006 to Oct. 15, 2006 in which Adjutant, a former prostitute initially from Swampscott, recruited three young girls, ages, 19, 20 and 22.Adjutant set them up at various motels in Saugus, Revere and Peabody and paid for the motel rooms.The prostitutes told authorities they charged the customers $150 to $200 for the sex acts and that the money was given to Adjutant or to Jones.One of the girls, living with Jones, told authorities she went to New Hampshire for one night and received the largest fee ever, $6,000, which she turned over to Jones, Hickey said.Another one of the prostitutes received drugs from Adjutant in exchange for the service she rendered for them and another said she sometimes had 10 to 15 customers a night, according to Hickey.The girls involved in the ring were not present during the plea hearing, but the judge ordered that Adjutant and Jones not have any contact indirectly or directly with them as Hickey explained to Whitehead their concerns for their own safety.In asking the judge to impose the same punishment of eight to 10 years for both of them, Hickey pointed out that Adjutant had been convicted of voluntary manslaughter, received a six-year sentence and had only been out a couple of months when sh