RI's beach access law attracts another lawsuit, this time from Westerly. What it claims.

Waterfront property owners in Westerly have filed a new lawsuit challenging Rhode Island's beach access law, arguing that it violates the separation-of-powers doctrine.

Last week, a federal judge tossed out an earlier challenge to the law by a different group of homeowners on the grounds that it didn't belong in federal court.

The new lawsuit was filed in state court Monday. The plaintiffs are David and Linda Roth of West Hartford, Connecticut, and ES710 LLC, which belongs to the Roths' two children.

Since 1988, the Roths have owned a 3.62-acre parcel at 3 Niantic Ave. in Westerly, overlooking East Beach. In 2011, their children's LLC acquired an adjoining 13.79-acre parcel of parcel at 7 Niantic Ave., the lawsuit states.

"The boundaries of each property encompass an upland area where residential buildings and other improvements are located, as well as dunes and a section of private beach that plaintiffs use for personal and family enjoyment," the lawsuit says. "Each property’s deed designates the Atlantic Ocean as the property’s southerly boundary."

What's new in this lawsuit

The lawsuit, which was filed in Washington County Superior Court, makes the familiar argument that Rhode Island's shoreline access law constitutes a "taking" of private property.

But it also makes the case that the General Assembly overstepped by overruling the judicial branch.

The background: For hundreds of years, Rhode Island's Constitution has guaranteed the right to use the shoreline, but it doesn't say anything about where those rights can be exercised.

Faced with that question in a case known as State v. Ibbison, the Rhode Island Supreme Court ruled in 1982 that the mean high tide line functioned as the boundary between public and private beach.

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In recent years, however, advocates drew attention to the fact that the mean high tide line – a highly scientific measurement – was impossible for the average person to find, and in many places was underwater for much of the day.

In response, the General Assembly passed a new law that states that the public has the right to use any beach as long as they're no more than 10 feet above the last high tide line, commonly known as the "seaweed line" or "wrack line."

The Westerly homeowners' lawsuit argues that legislators shouldn't have done that, because it's not the legislature's job to interpret the state's Constitution.

"It is a fundamental principle of constitutional law and the separation of powers that the interpretation of the federal and state constitutions is reserved for the judiciary, not the legislature," the lawsuit states.

Under the separation of powers doctrine, the General Assembly can't overrule the Ibbison decision, it argues.

The lawsuit also says that delegates to the 1986 Constitutional Convention considered amending the Constitution to define the shore as "that area below the tidal high water or vegetation line," but decided to leave that to judicial interpretation.

The plaintiffs are represented by Gerald J. Petros and Mackenzie C. McBurney of Hinckley, Allen & Snyder.

This article originally appeared on The Providence Journal: RI beach access law challenged by another lawsuit from Westerly