Neighbors of a convicted sex offender are seeking tax breaks on their homes.

Some two dozen homeowners in the Fox Run Drive area believe their property values dropped last fall when David Pollitt moved to his sister's home in their neighborhood.

They tried but can't force Pollitt to move out, so they have asked the town to reduce their property tax assessments by as much as 17 percent.

They argue the presence of a registered sex offender has lowered the sale price of their homes.

Pollitt, 54, was released in October after more than 24 years in prison for a series of rapes.

Carolyn Nadeau, president of the Connecticut Association of Assessing Officers, said the request may be the first of its kind in the state.

"I've never had an instance like this," she said. "Any number of times there are distractions that people feel negatively impact their property values, such as unsightly blight, but we haven't seen this."

The company that revalued all properties in Southbury last fall rejected the residents' plea for help. The new values took effect Oct. 1 and Pollitt didn't move to the neighborhood until Oct. 12.

Residents plan to take their case to the Board of Assessment Appeals in March.

Mark Lynch, who lives next door to Pollitt's sister in a house assessed at $243,080, believes residents deserve a break.

"If I wanted to sell my house tomorrow morning, how many people would want to buy it?" Lynch said.

Homes are assessed at 70 percent of their fair market value for tax purposes.

Woodbury real estate agency owner Joyce Drakeley said her agents would tell a client if a house was in a neighborhood with a sex offender, but the issue has not come up. Sex offenders must register with the state and the registry, including addresses, is available online.

"Buyers are not coming in and saying, 'Tell us if there are sex offenders in the area,"' she said. "I think it would affect the housing price if the buyers knew who was in the area. [The seller] has fewer people to sell to."