A 17-year-old who was arrested in relation to the same investigation also appeared in the court, where he faced separate charges.
Keith Hall, aged 23, from Kilmartin Drive, Tallaght, Dublin, was charged with the murder of Ms McCarthy, aged 16, and with possession of a firearm — a double-barreled sawn-off shotgun — with intent to commit an offence.
The parents of Christopher Moran, Ms McCarthy’s boyfriend, shouted abuse at Hall during the hearing at Tallaght District Court.
The court was told by Detective Garda Mick McGrath that the defendant did not reply when charged.
Melanie McCarthy was shot on Feb 7 as she sat in a parked car on Brookview Way, Tallaght. She died the following morning. Her boyfriend was in the front passenger seat.
Yesterday Hall’s solicitor, Michael Staines, said his client wished to apply for legal aid.
Judge James McDonnell requested a statement of means, which, after a brief adjournment, was supplied to the court.
Judge McDonnell granted legal aid and remanded Hall in custody to appear before Cloverhill District Court on Feb 28.
The 17-year-old boy arrested by gardaí investigating the murder also appeared in court, but was not charged on any matter in connection to the murder.
He was brought before the court in relation to three different sets of charges.
Two sets of charges related to outstanding bench warrants that had been issued against him following his failure to appear in court.
One set of warrants related to possession of heroin and possession of heroin with intent to supply — charges to which he has pleaded guilty.
Judge McDonnell said he would sentence him on these matters next week.
In the same bundle, there were warrants in relation to possession of shotgun cartridges and possession of a shotgun, but Judge McDonnell said the directions of the DPP were outstanding on these matters. A second set of warrants related to other charges, including theft and road traffic.
Det Gda Kieran McGrath also presented new charges to the court: Possession of cannabis resin and possession of cocaine for sale or supply.
Gardaí objected to bail, but his solicitor said there was no application for bail.
Judge McDonnell remanded the juvenile in custody to St Patrick’s Institution to appear before him again next Tuesday.
His father sat near him in court and they exchanged some words together.