TORONTO -- Ontario municipalities are keeping a close eye on provincial police contract negotiations to see if the province can whittle out years-of-service bonuses that communities say are becoming difficult to afford.

The benefit, known as retention pay, began in Toronto a little over a decade ago. The Ontario Provincial Police followed suit soon after, and over the years it found its way into most police and firefighter contracts across Ontario as recognition or service pay.

It gives an extra three-per-cent pay after about eight years of service, six per cent after about 17 years and nine per cent after about 23 years. In Toronto, the base pay of a first-class constable is $92,433.

Though the provincial government does not control the deals municipalities reach with their police services, it can set trends with the agreements it strikes with the Ontario Provincial Police.

As the Liberal government tries to eliminate a $10.9-billion deficit it has said any public-sector contracts must have "net zero" increases, so any small compensation boosts would have to be offset.

Neither the government nor the Ontario Provincial Police Association would say if retention pay -- also known as 3-6-9 -- is on the table as they bargain a new deal.

But most police service boards are hoping it is, says their provincewide association.

"Today, 3-6-9 does not serve a practical purpose," says Fred Kaustinen, the executive director of the Ontario Association of Police Service Boards.

Kaustinen said police forces have not faced retention issues for some time now, and there are no performance-related benefits associated with 3-6-9.

"The only impact or relevance...is to increase the pay of long-serving police officers and increase the cost of the overall police wage envelope across Ontario by roughly 4.5 per cent."

The president of the Police Association of Ontario says the bonus pay may be the reason why retention issues no longer exist. It has now become part of the negotiated salary, says Bruce Chapman.

"It's a dangerous profession and it's part of their overall compensation package, which fairly reflects the duties and the work that they do," he says.

Firefighters also receive bonus pay, but the head of their union says it's more a benefit for years of service than an incentive not to move elsewhere.

"It's unfair for pretty much the same type of first responder protection services that we provide and police provide that we be paid any less than a police service," says Carmen Santoro, president of the Ontario Professional Fire Fighters Association.

In Toronto, the chair of the police services board refused to be interviewed, but in a 2011 letter to then-premier Dalton McGuinty he blamed the provincial government for the practice's spread across Ontario. Toronto had a retention problem -- the OPP didn't, Alok Mukherjee wrote.

"Other police services had settled their contracts after Toronto without giving it, but once the province made it a provincewide feature, all of the other police services subsequently followed," he wrote.

"Our province has a long history of driving up the costs of policing through deals given to the OPP."

The mayor of Stratford says municipalities are finding it tougher than ever to fund emergency services -- nearly 40 per cent of the tax levy in his small city goes toward them -- and clauses such as 3-6-9 need to be taken into account.

"It's not affordable, nor is it sustainable," says Dan Mathieson.

In Stratford, the clause was first included in the negotiated settlement for police in 2009. The city could have gone to interest arbitration over 3-6-9, but since it was already in other comparable police forces across Ontario, there's no doubt the arbitrator would have awarded it anyway, Mathieson said.

If negotiated contracts can't be reached with emergency service workers, disputes are settled at interest arbitration because they don't have the right to strike.

The Association of Municipalities of Ontario has been pushing for years for changes to the system, arguing that arbitrators place greater priority on replicating agreements from similar communities over local fiscal circumstances. Private member's bills have made unsuccessful attempts at changing the system.

The municipalities want to see stronger fiscal criteria for determining capacity to pay as police and fire budgets are on the rise, says Jeff Lehman, the mayor of Barrie and chair of the Large Urban Mayors' Caucus of Ontario.

"Whether it's 3-6-9 or other issues, whether benefit or compensation based, the broader issue here for all of us is the financial sustainability of the kind of increases we've seen," he says.

The Liberal government says it is "continuing to assess options to reform the interest arbitration process."