What are certificates of participation?

Essentially a mortgage on the project they are funding. The government uses the land and buildings as collateral for investors who lend the money.

General obligation bonds, which are typically issued to build schools and buy open space, must be approved in a referendum. Certificates of participation, sometimes called COPs, do not require voter approval.

Since they are not backed by the government's taxing power, they come with a slightly higher interest rate, making them a more expensive way to fund projects. 

In North Carolina, COPs have been used to build jails, parking decks and convention centers. In recent years, they have also become a popular way for North Carolina counties to build schools.

Around the Triangle, certificates of participation have paid for the Durham Bulls Athletic Park, the new Raleigh convention center, the Fayetteville Street Mall renovation and a parking deck for a downtown Raleigh hotel.