The Criminal Assets Bureau's attempts to uncover the income of Mr John Gilligan's daughter was "like extracting teeth", a barrister for the Department of Social Welfare has alleged.
Mr Gilligan has been accused of the 1996 murder of the journalist Veronica Guerin.
Ms Nuala Jackson told Dublin Circuit Court that Ms Tracey Gilligan had consistently failed to provide adequate details of her income to CAB officers.
She also said that Ms Gilligan's barrister, Mr Padraig Dwyer, distanced his client from her parents when it suited, yet relied upon her connection to them when trying to show bias against her. Ms Jackson was speaking on the fifth day of Ms Gilligan's application to have her lone parent's allowance reinstated.
Ms Gilligan (25), of Wills brook, Lucan, had the allowance withdrawn in December 1996. She applied in March 1998 to have it reinstated but her application was rejected.
Officers from the Department of Social Welfare who are attached to CAB gave evidence that Ms Gilligan had not provided adequate information.
Ms Jackson said it was not a criminal case. It was Ms Gilligan's application and she would have to prove her case.
Ms Gilligan concealed several cash lodgments which might have come from her father. There were several legitimate queries by CAB officers which she had not responded adequately to.
Judge Elizabeth Dunne said that Ms Jackson was being "somewhat unfair" to Mr Dwyer but said that while there were certain "unpalatable facts" about Mr John Gilligan, it should not prevent CAB officers from carrying out their duty.
Judge Dunne said she hoped to reach a decision on Ms Gilligan's claim by the end of the legal term. She said she very much regretted that evidence in the case had been broken up over a number of months.