(a) Joint or joint and several tort-feasors, obligors, or promisors, or joint contractors or copartners, residing in different counties, may be subject to an action as such in the same action in any county in which one or more of the defendants reside. If, however, the court determines prior to the commencement of trial that:

(1) The plaintiff has brought the action in bad faith against all defendants residing in the county in which the action is brought; or

(2) As a matter of law, no defendant residing in the county in which the action is brought is a proper party,

the action shall be transferred to the county and court which the plaintiff elects in which venue is proper. The burden of proof on the issue of venue shall be on the party claiming improper venue by a preponderance of evidence.

(b) If all defendants who reside in the county in which an action is pending are discharged from liability before the commencement of trial, a nonresident defendant may require that the case be transferred to a county and court in which venue would otherwise be proper. If venue would be proper in more than one county, the plaintiff may elect from among the counties in which venue is proper the county and the court in which the action shall proceed.

(c) If all defendants who reside in the county in which the action is pending are discharged from liability after the commencement of trial, the case may be transferred to a county and court in which venue would otherwise lie only if all parties consent to such transfer.

(d) For purposes of this Code section, trial shall be deemed to have commenced upon the jury being sworn or, in the instance of a trial without a jury, upon the first witness being sworn.

(e) Nothing in this Code section shall be deemed to alter or amend the pleading requirements of Chapter 11 of this title relating to the filing of complaints or answers.

(f) This Code section shall apply to actions filed on or after July 1, 1999.