The 33-year-old, who cannot be named, appeared at Central London County Court today (March 24).
The domestic violence victim romped with PC James Formby, 34, of Maidstone, after he and another officer responded to her 999 call in September 2009.
She had been clubbing in Bromley when her boyfriend, a male stripper, is alleged to have beaten her up on the street.
Formby stayed behind to get a statement after the man was arrested and is said to have later followed the woman into her toilet.
She then performed a sex act on him after she allegedly asked Formby to kiss her.
Formby later sent her a text message saying he wanted to "do this again", but the woman reported the incident.
The court heard how she is seeking £4,730 to £15,400, plus a further £11,000, if it is found that she did not have the capacity to consent to the sexual activity.
Ruth Brander, for the woman, said: “The claimant claims damages, including aggravated and exemplary damages, in respect of misfeasance.”
She said the Met Police commissioner was liable after Formby “abused his position of trust as a police officer by engaging in sexual activity with her whilst he was on-duty as a uniformed police officer”.
The court was told the claimant was intoxicated at the time and, after sobering up and reflecting on what had happened, became “increasingly concerned and distressed”.
In September 2010 she was diagnosed as having a depressive and anxious adjustment disorder as a result of Formby's conduct, it is claimed.
Barrister Jonathan Loades denied the Met commissioner is liable and told Judge Edward Bailey: “We need you to decide whether this happened in the course of his work as a police officer or on a frolic of his own, which was completely separate to his purported performance.”
The former officer, who was given a 20-week prison sentence suspended for two years in March 2010 after admitting a single count of misconduct in a public office, is set to give evidence tomorrow (March 25).
The case continues.