The federal government would like to build a halfway house for federal prisoners in Manchester. But the plan is not going over very well in the city. Several of the city’s aldermen oppose the idea. So does Manchester’s chief of police. Among their top concerns, they worry that a halfway house would bring in more crime, and make the community a less desirable place to live. But proponents are working hard to dispel those preconceptions. And they point out that while this issue may be new to Manchester, halfway houses exist in cities across the country. New Hampshire Public Radio’s Rebecca Kaufman reports.