A Dublin mother-of-four, who claimed she did not know her Las Vegas marriage was valid in Ireland, has been cleared of unlawfully obtaining almost €30,000 in one parent family social welfare payments.

At Dublin District Court, Judge John Brennan had compared the case to the 2009 comedy film ‘The Hangover’, about the antics of a group of men at a bachelor party in Las Vegas.

Judge Brennan said the marriage was valid.

However, he accepted submissions from Matthew Holmes BL that his client, 39-year-old Michelle Burke, from Cappagh Road, Finglas, could rely on the defence of "honest though unreasonable belief".

Dismissing the case, the judge said he had studied her demeanour when she testified and he added that her evidence was effectively uncontroverted.

The total alleged fraud was €29,773 and it was the prosecution's case that she got married and failed to notify the Department of Social Protection while claiming the one parent family payment between November 2010 and August 2012, a charge she had denied.

If convicted she would have faced a possible six-month jail term.

The district court trial heard she had been in receipt of the one parent family payment since 1997.

Evidence was given in March and Judge Brennan had adjourned the case until today to give his verdict.

The court had heard that the accused was getting €317 a week.

People who have children but do not have support of a partner were eligible, however, if they got married or entered into a civil partnership their entitlement ended, social welfare inspector Helen O'Reilly had told the court.

She told the trial that in 2011 and in 2013 reviews were conducted and Ms Burke was sent forms inquiring if her circumstances had changed but she signed declarations that she had not got married nor was she living with a partner.

The social welfare inspector told Judge Brennan there was a suspicion Ms Burke may have been cohabiting with a partner.

An investigation commenced and the inspector was able to obtain a copy of a marriage certificate from the United States.

She said it confirmed Ms Burke got married to her current partner on 6 November 2010, at the Holywood Wedding Chapel, Las Vegas in Nevada.

The Clark County marriage certificate had her date of birth and address as well as that of the man she married.

The court heard the certificate was a public document and the marriage was legally recognised in Ireland.

Her payment was stopped and she was interviewed but told the inspector she did not think that the marriage was legal.

She also said her partner, who was not the father of her children, paid tax and then lived at a different address in Dublin 1.

The inspector told defence counsel Matthew Holmes BL the marriage was legally binding for the purpose of social welfare.

She also agreed the defendant and her partner were now claiming a family allowance.

Following legal submissions over the validity of the US marriage documents furnished to the court, Judge Brennan accepted the certificate was evidence of what was recorded.

In the witness box, the mother-of-four had claimed she had gone to America for a few days with a group of 16 or 17 for a 30th birthday party for her brother's friend.

Questioned by her barrister about the marriage ceremony she claimed "we just thought it was funny to do it" and it was "for a laugh". "I honestly didn't think it was legal," she said.

Asked why she did not remember much about the ceremony, she replied, "because we were drunk".

She also said she could not remember much about the ceremony but she agreed the certificate had her address and date of birth as well her partner's details, and that they had to hand over their passports beforehand.

Ms Burke repeatedly told the court she did not mention it to the social welfare office because she did not think she was really legally married.

She also agreed the marriage cert had the names of the country clerk and the witnesses at the wedding and that her partner had not been living with her at the time of the alleged offences.

Mr Holmes, defending, cited a Supreme Court ruling by Mr Justice Charlton that an "honest though unreasonable belief" was a defence.

Mr Holmes argued that at all times the woman has stated that it was her belief that the marriage was not legal and "an innocent act is always a defence".