Massachusetts’ highest court yesterday rejected Cambridge’s demands for a redistricting plan that does not place the city in six state House of Representatives districts.

The ruling ends Cambridge’s legal efforts to minimize the division of the city.

The redistricting plan, adopted by the state legislature in 2001 for use starting in this fall’s elections, includes parts of Cambridge in six different House districts. Only one of these districts is solely within Cambridge, with the other five combining the city with parts of surrounding cities.

The districts used from 1994 to 2000 divided Cambridge primarily into three House districts—two of which were entirely within the city. A tiny portion of the city was part of a fourth district.

“The plan unconscionably divides our city into six separate districts over the opposition of the Cambridge delegation,” said Rep. Jarrett T. Barrios ’90-’91 (D-Cambridge).

The plaintiffs—Cambridge’s mayor, city council and 11 registered voters—had argued in court on March 7 that the redistricting plan violated the provision in the state constitution requiring that legislative districts be formed “as nearly as may be” without combining parts of different cities and towns. They also claimed the redistricting would dilute the voting power of Cambridge’s minority residents.

But the Supreme Judicial Court ruled that the plaintiffs did not prove beyond a reasonable doubt that the redistricting plan violated the state constitution.

The court concluded in its 18-page opinion that the various districting guidelines mandated by federal and state law “create a conflict that cannot be perfectly harmonized in every case and is left primarily to the Legislature to resolve.”

The court cited its “substantial deference” to the legislature in making this decision.

Since the legislature must district for the whole state, the court wrote local concerns were not as important as overall state goals in redistricting.

The court also ruled that the redistricting plan did not violate the federal Voting Rights Act of 1965. That act forbids the creation of districts that spread minority voters among several districts so their voting power is diluted. The act also prohibits “packing” minority voters into a single district so minorities cannot exercise electoral power in several districts.

The 28th House District—which had only included Cambridge voters—contained a large minority population and had a long history of electing minority representatives.

“We had a district that was more likely to elect a minority even though it was not a minority-majority district, as evidenced by the last three holders of the seat,” said Mayor Michael A. Sullivan.

But after Barrios, who currently represents the 28th district, decided to seek a seat in the state senate, House Speaker Thomas M. Finneran (D-Boston) split the voters of this district into several others.

Barrios attributed Finneran’s decision to his desire to weaken the power of Cambridge voters who typically elect progressive representatives. Finneran is known for his tight control over the legislature and conservative views.

But others—including fellow legislators—placed blame on Barrios for the loss.

“He made the decision to run for higher office,” said Rep. Paul C. Demakis (D-Boston) this fall. “That made his district vulnerable, and then he did very little to try and preserve his seat.”

Cambridge had presented the court with several alternative redistricting plans, which would have divided Cambridge into three districts instead of six. The court ruled not to consider these plans, but only evaluated whether the state plan was “reasonably justified” under federal and state law.

The adjacent town of Watertown and the Cambridge Democratic City Committee filed briefs arguing in favor of Cambridge’s case.

The City Council held a closed executive session last night specifically to discuss the outcome of the redistricting case. The meeting lasted only about 15 minutes.

Councillors at the meeting concluded that they could not take their case against the state any further, Sullivan said.

“It’s the state’s highest court ruling on a state issue,” Sullivan said.

Although Cambridge had included federal constitutional and statutory issues in the lawsuit, the city cannot appeal the case to federal courts, Sullivan said.

“We pursued our best shot with the state law,” Sullivan said.

—Staff writer Stephanie M. Skier can be reached at skier@fas.harvard.edu.