A would-be duck boat competitor is waging amphibious warfare against Boston police, firing a salvo of two lawsuits claiming that cops have unconstitutionally thwarted its fleet from taking the plunge.

Nautical Tours Inc. argues in parallel state and federal lawsuits that BPD’s Hackney Carriage Unit has refused to act on the company’s pitch to license nine water-ready tour vehicles. The company has been attempting to get fully licensed since 2003, and its attorneys argue that Boston police Commissioner William B. Evans and the Hackney Carriage Unit haven’t responded in three years. Nautical is seeking to compete with Boston Duck Tours, which has been operating since 1994.

“The three-year delay without any explanation is, in itself, a deprivation of the constitutional right to due process,” said Joseph Comenzo, an attorney representing Nautical Tours. “Even if there is a denial, there needs to be some action.”

The suits claim that Nautical Tours has already received three of the four licenses it needs to operate its tour and that BPD has singled out the company by dragging its feet. The suit claims that in a 2015 meeting on the holdup, a police lieutenant said, “Well sometimes things move along more quickly when you know the right people.”

A police spokesman declined to comment on pending litigation.

As a result of the prolonged process, Comenzo claims in the federal suit that his clients have suffered damages, including “lost financial support of investors, humiliation and emotional injury, as well as harm to their professional and commercial reputation.”

On its website, Nautical claims it will offer a 90-minute tour on its “Amphicoach amphibious tour bus” that will take tourists around some of the familiar landmarks in Boston and Cambridge. But, for now, the fight over valuable licenses has left Nautical’s fleet high and dry.

“We’ve been trying to navigate the licensing requirements with the city of Boston for a long time,” Comenzo said. “It would essentially compete with Duck Tours, but it’s just one more license.”