Discussing a recent Court of Appeal decision, which dismissed the DPP's appeal against a decision to disqualify evidence in a criminal trial that had been obtained with invalid search warrants, the LIV has again highlighted the widespread practice amongst police of obtaining warrants with unsworn affidavits - and the need for this system to be reviewed.

"This is not just a random administrative oversight. The problem appears to be systemic and needs to be challenged," said acting LIV president Michael Holcroft.

"Police must immediately make renewed efforts at following proper procedure. This requires police to make sworn statements when they apply to a magistrate for a search warrant," he said.

Holcroft said the makers of the affidavit must appreciate the seriousness of the statement being made, be prepared to attest to its truth and be subject to the consequences if the information put to the court is not correct.

"Search warrants confer on police an extraordinary power to encroach upon a person's rights to protect their home and property from intrusion," he said. "For this reason, the evidence upon which warrants are based should be of the highest standard. If police continue to fail to follow proper procedure, then the system needs reviewing.

"A chain of procedure has been established to determine the genuine cause for a search warrant. It is a key link in the prosecution process and failing to treat it seriously undermines the integrity of the law."