After three decades getting a discount, Red Bank tenants could have to pick up full cost-of-living increases starting later this year.

The borough council introduced an ordinance change Wednesday night that would allow landlords to increase rents by the full amount of the Consumer Price Index published by the federal Labor Department.

Since as far back as 1978 or even earlier, local increases have been capped at 60 percent of the CPI rise when a tenant pays for heat, and 80 percent when the landlord does.

The reason for the change, said Mayor Pasquale Menna, is that no one can remember the rationale for the discount, and no paper trail for it exists, leaving it open to a lawsuit.

“If it were challenged, we would not prevail,” said Menna, an attorney who made his political bones as a tenants’ advocate in the early 1980s. “It’s defective.”

The borough is also out of compliance with a state law requiring towns with rent control laws to review their ordinances every five years, Menna said. In Red Bank, “it hasn’t been done in at least 20 years,” he tells redbankgreen.

The glaring inconsistencies came to light at an October meeting of the Rent Leveling Board, which enforces the ordinance and adjudicates disagreements between landlords of multifamily residences and tenants. Landlords had previously appealed to the council to be freed of the CPI cap.

At that meeting, a senior citizen expressed concern about the impact of full CPI increases on renters living on fixed incomes.

Menna said the amended ordinance, if passed, would require the rent board to review the law every two years.

Here’s the proposed amendment: 2012-7A hearing and possible adoption are scheduled for April 11.