Trial for a Lawrence man charged with exposing multiple women to HIV has been put on hold because of a constitutional challenge to the law he’s charged with breaking.

The first of four HIV-exposure trials for 30-year-old Robert W. Richardson II was scheduled to begin today, but prosecutors dropped the case in a hearing Tuesday morning in District Court. Dist. Atty. Charles Branson said he also plans to drop Richardson’s three other pending cases – but all four cases will be re-filed as soon as today and consolidated into one case.

Defense attorney Thomas Johnson filed a motion Aug. 7 arguing that the state law Richardson is charged with breaking – a felony called “exposing another to a life-threatening communicable disease” – is overly broad and unconstitutional.

“All sex by persons who have knowledge that they are infected by a life-threatening disease is subject to prosecution,” he wrote. “A statute this broad would be violative of an individual’s liberty rights and due process.”

Robert W. Richardson II was charged with exposing four women to HIV in Douglas County. The charges have temporarily been dropped, but prosecutors plan to consolidate all four cases into one and refile charges.

Branson said his office now needs more time to research the law, which apparently has never been tested despite being on the books since the early 1990s.

During a pretrial hearing Monday, prosecutors asked for the first trial to be delayed to give them more time to respond to Johnson’s motion, but Judge Stephen Six denied the request.

“This case will be tried,” Branson said Tuesday. “The constitutionality of this issue is going to be decided. The only thing this is is the process. This has nothing to do with the strength or weakness of either side’s case.”

The law was enacted in the early 1990s, but Branson said it appeared this would have been the first time a case charged under the law had gone to trial.

He said his attorneys needed more time to research the history of the bill, legislators’ intent in drafting it and similar laws in other states. Regardless of which side wins, he said, the case is bound to be appealed.

“We believe that it’s appropriate for us to put together the best arguments that we can,” he said.

Richardson remained in jail Tuesday evening and has an HIV-related case pending in Lyon County with bond set at $50,000. Branson said Richardson would have a new bond set in the consolidated Douglas County case.