LITTLE ROCK — The group sponsoring a ballot issue that would limit damages in medical lawsuits is alleging that the secretary of state’s office incorrectly threw out some valid signatures that were submitted in support of the measure.

Health Care Access for Arkansans made the allegation in a cross-claim it filed Wednesday with the state Supreme Court in a lawsuit brought by opponents of the measure who are seeking to have it stricken from the November ballot.

If approved by voters, Issue 4 would amend the state constitution to limit a trial lawyer’s contingency fee to 33 1/3 percent of the amount recovered in a medical-injury case and direct the Legislature to set a cap of no less than $250,000 on non-economic damages against health-care providers. Non-economic damages are damages for things other than monetary losses, such as pain and suffering.

In its suit challenging the measure, the Committee to Protect AR Families alleges that Health Care Access for Arkansans did not comply with state laws governing the use of paid canvassers and that the ballot title is misleading and does not fully explain the proposal to voters.

Secretary of State Mark Martin certified the measure for the ballot after his office determined that at least 92,997 of the signatures submitted in support of the proposal were valid signatures of registered Arkansas voters. The proposed amendment needed at least 84,859 signatures to qualify for the ballot.

In its cross-claim filed Wednesday, Health Care Access for Arkansans said Martin “incorrectly deemed some signatures or the petition parts on which they appear as invalid and thus did not include them in the total number of signatures. Those signatures should have been counted and should now be counted by the court.”

Fairness for Arkansans, a group created by the Arkansas Bar Association to oppose Issue 4, has filed a separate lawsuit that also alleges the measure’s ballot title is deficient but does not challenge signatures submitted in support of the proposal.