Opening statements in the aggravated assault and battery trial of Russell Tillis will begin on Tuesday morning.

Tillis is the same man accused of murdering and dismembering a woman at his Southside property, dubbed by neighbors a “House of Horrors.”

Tillis will be tried for the murder at a later date.

Jacksonville criminal defense attorney Janet Johnson, who is not affiliated with either Tillis case, said attorneys have to keep the two cases separate or else it could lead to a mistrial.

“If they get up there and say ‘This man’s also going to be tried for murder or is suspected of a murder,’ that is not okay and the judge would probably declare a mistrial,” Johnson said.

However, Johnson said if Tillis is convicted of the assault and battery charges, it could be used against him in the murder trial.

“It’s pretty damaging for a defendant to have a felony conviction used against him if he’s going to testify,” Johnson said. “The jury would be told in deliberation that they can weigh that in deciding whether his testimony was honest and truthful.”

If the jury clears Tillis of the assault charges, it could also impact what evidence can be admitted in the next trial.

Police said Tillis confessed to the murder of 31-year-old Joni Gunter to another inmate while jailed on the assault and battery charges. If Tillis is found not-guilty of the initial charges, Johnson said his attorney could argue for the confession to be thrown out for the murder trial.

“To say ‘Since he was unlawfully arrested, you shouldn’t have had him in the Duval County Jail. Anything he said in the Duval County Jail shouldn’t be used against him in another case,’” Johnson said.