A grandmother has fought back tears in court as she testified against a policeman accused of raping her daughter.

The woman, who cannot be named for legal reasons, sobbed as she told the High Court in Aberdeen how her daughter had been allegedly attacked in her own house, while children slept in the next room.

Andrew Robertson, 49, is said to have raped the young mother on a sofa at her Aberdeenshire home in January 2012 while his long-time partner Elaine Duncan held her down.

The officer denies the offence and has lodged a special defence of consent.

The court heard that the woman told her mother that a drunken night of "capering", "strip tease' and "games" had gone wrong.

The mother said: "She told me that she thought she had been raped but that she couldn't remember all that had happened the night before.

"She told me Elaine pulled her down on the sofa and she struggled to try and get away but she couldn't and Andy raped her.

"And then afterwards, after they had done what they wanted to do, Elaine went into the bathroom then came out and started hitting her and accusing her of having an affair."

Mr Robertson, from Aboyne, Aberdeenshire, is accused of restraining the woman with another person, seizing hold of her arms, preventing her from moving and raping her on January 14 2012.

The woman claimed she and Ms Duncan had been drinking at her house on January 13 but the mood had changed when Mr Robertson turned up.

The woman claimed Robertson and Ms Duncan started making comments a threesome.

The court heard said she was intimidated into stripping off after which Ms Duncan held her down while Robertson raped her on the sofa.

Photos of both women showing their breasts were later recovered from Robertson's phone.

Ms Duncan denied that her partner had raped the woman, but claimed the sex was consensual.

The 48-year-old claimed that the woman had initiated the "games".

Ms Duncan told the court she had went to the bathroom after becoming uncomfortable when both Robertson and the woman removed their clothes.

When she came back and stood in the doorway she found her partner having sex with the woman on the couch. She said the woman seemed quite happy. She denied pinning her down.

The trial, before Lord Turnbull, continues.