Police in Northern Ireland had not been trained in seizing organised criminals' cash two years after the measure was ordered, a watchdog said.
More than £2 million was confiscated by the courts last year, but a murder by IRA members allegedly cooperating with organised criminals has shone a fresh light on the problem.
The Police Service of Northern Ireland (PSNI) said training had taken place recently against a backdrop of reduced budgets.
Douglas Bain reviewed proceeds of crime legislation in Northern Ireland.
He said: "It is very regrettable that, having identified a training need two years ago, no adequate training or information on these matters had been provided to PSNI officers by the end of the reporting year."
Section 289 of the Proceeds of Crime Act empowers constables and other officials, in prescribed circumstances, to search property and persons for cash. Cash is widely defined.
Section 290 provides that appropriate prior approval must be obtained, unless impractical, for any such search from a justice of the peace.
A new code of practice is planned.
Mr Bain said it was unrealistic to expect most front line officers to have a full understanding of their powers and duties under sections 289 and 290 of the Act.
But he recommended that PSNI provides appropriate training to officers.
Northern Ireland Secretary Theresa Villiers has said she will establish a fund to tackle crime associated with paramilitary groups following the killing of Kevin McGuigan, which has rocked the political institutions.
Mr McGuigan is suspected to have been shot dead by organised criminals, dissident republicans opposed to the peace process and members of the IRA. Revelations that the IRA still exists have seen unionists threatening to withdraw from powersharing and an urgent review of paramilitarism by the Government.
Fuel fraud, using the Irish border to sell laundered agricultural diesel to motorists and evade excise duty, is a lucrative money spinner in parts of Co Armagh.
An Organised Crime Taskforce report earlier this year said, over the previous 12 months, more than 600,000 litres of illegal fuel were seized and 27 laundering plants dismantled.
More than 5,000 drug seizure incidents and 2,800 drug-related arrests were recorded. A total of 45 potential victims of human trafficking were recovered.
Detective Chief Inspector Ian Wilson, from the Economic Crime Unit, said: "Training in relation to the Proceeds of Crime Act has taken place since the period of the report and a further programme of training is planned for the next twelve months.
"This is being considered against a backdrop of a reduction in budgets and our commitment to policing priorities."