PHILADELPHIA (AP) – Conflicting interpretations of the state constitution drove the discussion before Pennsylvania's high court Thursday, as the justices considered a new redistricting plan that would govern legislative elections for most of the next decade.

The state Supreme Court rejected the Legislative Reapportionment Commission's original plan in January, after citizen challengers presented spreadsheets that convinced a majority of the justices that the plan split up too many municipalities and produced districts that were not sufficiently compact.

The 4-3 ruling resulted in this year's elections being based on maps drawn in 2001. The proposal now under consideration would not take effect until the 2014 election.

At the hearing in the City Hall courtroom, lawyers for many of the dozen challengers said the Republican-controlled commission's latest plan still calls for too many splits of counties, municipalities and wards to satisfy the constitution's requirement that divisions be avoided unless "absolutely necessary."

They also said the plan for the 203 House districts and 50 Senate districts did not go far enough in reshaping districts that the court cited in its earlier ruling as insufficiently compact and contiguous as required.

"The maps of Philadelphia still look like a piece of abstract art," said Stephen Loney, part of the legal team representing a bipartisan citizens group that was instrumental in defeating the first plan.

Justice Thomas Saylor and lawyers for the commission argued that politics not just mathematics play an important role in the redistricting that the constitution requires once every decade to equalize representation following each census.

Saylor called redistricting "intrinsically political."

"The process can't just be one of raw political power because it's constrained by the constitution equality, continuity, compactness but there's other factors that aren't in the constitution community of interest, partisan composition," he said.

Commission attorney Joseph Del Sole said the framers of the constitution envisioned a political role in redistricting because four of the five seats on the commission are reserved for party leaders from each house.

"This is the process that the people of Pennsylvania accepted and approved. It is a political process," Del Sole said.

Senate Minority Leader Jay Costa, who cast the only commission vote against the plan, and his 19 fellow Senate Democrats also filed a court challenge that cited unnecessary splits and less-than-compact districts as a purely political attempt by the GOP to enhance its members' re-election prospects.

"They are gratuitous splits. They are obviously done for partisan gain," said the Democrats' lawyer, Clifford Levine.

Chief Justice Ronald Castille, a Republican who joined with the three Democratic justices in rejecting the original plan, generally stayed out of the discussion.

The court is now evenly divided between three Republicans and three Democrats, with a vacancy created by the May suspension of Republican Justice Joan Orie Melvin. She faces a trial on corruption charges.

The commission is led by a chairman picked by the legislative members or, if they cannot agree, appointed by the Supreme Court. Superior Court President Judge Emeritus Stephen McEwen, a Republican, was named commission chairman by the court.