A teenage girl tried to smuggle cannabis into a young offenders’ institution for her boyfriend by hiding it in her bra, a court heard.

Sinead Lillywhite-Doyle was rumbled after a sniffer dog at HMP Rochester “indicated” her left breast.

The 18-year-old at first denied having any drugs on her but when taken to a room to be searched she produced three wraps of cannabis from her bra.

Police then searched her bedroom at her home and discovered cocaine and heroin in a Tampax box in a chest of drawers.

Lillywhite-Doyle admitted taking drugs into prison and two offences of possessing drugs with intent to supply.

“Drugs are widespread in prison. That is a notorious fact. They are currency in prison”- Judge Joy

She was sentenced at Maidstone Crown Courtto 12 months youth custody after a judge told her she had been given several chances by courts.

Prosecutor Trevor Wright said Lillywhite-Doyle went to the prison on October 28 this year to visit her boyfriend, who was serving a sentence for wounding.

After the drug was seized she claimed she did it because her boyfriend and his family had been threatened.

Mr Wright said a search was then carried out at the teenager’s home and 10 wraps of heroin and eight wraps of cocaine were seized.

Rebecca Upton, defending, said although Lillywhite-Doyle had a lot of previous convictions she had none for drugs and had never found herself in such a position before.

She had a troubled childhood. Her parents separated when she was young and she lived with her father.

“Her peer group had a negative influence on her, encouraging her to drink and smoke cannabis,” said Miss Upton.

“It would appear this young lady has been taken advantage of. It has been her first time in custody.”

Judge Martin Joy told Lillywhite-Doyle, of Worthing, West Sussex: “For the last two-and-a-half years you have been out of control committing criminal offences,” he said. “The reality is these are extremely serious offences.

“Drugs are widespread in prison. That is a notorious fact. They are currency in prison.”

The judge said cocaine and heroin were deadly substances and those who deal in them had to expect serious punishment.

“They cause serious illness, they contribute to crime and they undermine society,” he continued. “There has to be a clear and consistent message.”

But Judge Joy said Lillywhite-Doyle’s accepted basis of plea that threats had been made and that she was holding the Class A drugs for others and intended to return them, was “a very significant document”.

He added: “You have been given chances. The time has come where there has to be an immediate sentence of detention.”