Fourteen volunteer firefighters under investigation in Montgomery County for alleged violations of the county's ethics code filed a suit yesterday asking the Circuit Court to remove County Executive Charles W. Gilchrist and five county ethics commission members from office, saying their civil rights were being violated by a political "witch hunt."

The volunteers, who do not deny their involvement in a county referendum campaign last year, claim the investigation violates their rights to free speech and to confront their accusers.

The suit names Gilchrist and the five commission members as defendents and asks the court for $550,000 in damages. The volunteers charge that the ethics commission proceeded in its investigation without a sworn complaint -- in violation of county ethics law -- solely to engage in a "witch hunt" and "political harassment campaign" against the firefighters and County Council member Esther Gelman.

The commission, whose members are appointed by Gilchrist and confirmed by the council, began the investigation in April after an inquiry was made by an individual who has not been publicly identified.

The individual questioned the propriety of efforts by Gelman and the firefighters to defeat two 1984 ballot questions that would have changed the way council members are chosen from an at-large election to voting by districts.

The confidential investigation became public last month after Gelman and Paul H. Sterling Jr., volunteer chief of the Wheaton Rescue Squad and a plaintiff in the suit, charged that the probe was politically motivated.

According to documents filed in the case, the commission's special counsel, Alexander J. Crow, asked Gelman, Sterling and 13 other volunteers for names of firefighters who posted campaign signs, whether supervisors ordered them to do so and whether they did so on county time with county vehicles, a violation of the county ethics code.