ATLANTA (AP) — A trial is set to get underway Tuesday on a lawsuit filed by Democrats challenging two new rules passed by the Georgia State Election Board that have to do with county certification of election results.

Supporters of the rules say they are necessary to ensure the accuracy of the vote totals before county election officials sign off on them. But critics say they worry that supporters of Republican presidential nominee Donald Trump could use the rules to delay or deny certification if the former president loses the state to Democratic Vice President Kamala Harris, causing confusion and casting doubt on the results.

The lawsuit is to be decided in a bench trial, which means there's a judge but no jury, before Fulton County Superior Court Judge Robert McBurney.

One of the rules provides a definition of certification that includes requiring county officials to conduct a "reasonable inquiry" before certifying results, but it does not specify what that means. The other includes language allowing county election officials "to examine all election related documentation created during the conduct of elections."

The lawsuit was filed by the state and national Democratic parties, as well as county election board members, Democratic voters and two Democratic state lawmakers running for reelection. It asks the judge to confirm that election superintendents, which are multi-person election boards in most counties, have no discretion to withhold or delay certification. It also asks him to declare the two new rules invalid if he believes they allow such discretion.

The lawsuit was filed against the State Election Board, which is dominated by three Republican partisans whom Trump praised by name at a recent rally in Atlanta. The state and national Republican parties have joined the lawsuit on the side of the election board.

While the Democrats concede that the two certification rules may not be counter to Georgia law, they argue the rules were drafted on the assumption that certification by county officials is discretionary. They worry that some officials allied with Trump could use the new rules to try to refuse to certify the election results by the deadline set in law.

Lawyers for the state argue that the Democrats are asking the judge to reinforce what is already in state law — that county certification must happen by 5 p.m. the Monday after the election, or the next day if that Monday is a holiday.

The Republicans who have a 3-2 majority on the State Election Board have used their power to pass numerous election rules in recent months, mostly over the objections of the Democratic appointee to the board and the nonpartisan chair. Secretary of State Brad Raffensperger, an association of county election officials and the state attorney general's office have all cautioned against adopting new rules so close to the general election, saying it could cause confusion and put unnecessary burden on election workers.

The new rules have drawn multiple lawsuits.

State and local Democrats, and some county election officials, on Monday filed a lawsuit challenging a rule that requires three poll workers to each count the paper ballots — not votes — by hand at polling places once voting ends on election day.

A separate lawsuit filed by a group led by a former Republican lawmaker initially challenged the two certification rules and was amended last week to also challenge the ballot-counting rule and some others that the board passed.