New Jersey Democrats are seeking to invalidate new rules adopted by the Christie administration that they say threaten to upend the foundation of the state's civil service system.

The state Civil Service Commission, composed of Christie appointees, last month adopted rules that changed the process by which employees in the executive branch are promoted. After taking initial exams to enter civil service, government employees are organized into so-called job bands, groupings of titles for those with similar duties and responsibilities.

Under the new rules, employees can advance to higher titles within those pools without additional tests. Critics say the exams are key to the meritocracy envisioned in New Jersey's 1947 constitution.

The administration has said the changes will improve efficiency while satisfying constitutional requirements that appointments and promotions in civil service be made "according to merit and fitness to be ascertained, as far as practicable, by examination."

Hetty Rosenstein, state director of the Communications Workers of America, said, "The entire concept and purpose of civil service is that anybody - your average person, anyone who wants to - can compete for a government job based upon their desire. And then, if they are most meritorious and fit, they will get the job."

"This turns that idea upside down on its head," said Rosenstein, adding that it would affect about 50,000 workers.

In their attempt to nullify the rule, Democrats are invoking a 1992 amendment to the constitution that says the Legislature may review rules and regulations to determine whether they are "consistent with the intent of the Legislature as expressed in the language of the statute which the rule or regulation is intended to implement."

Democrats said they used that power this year to block the rule and called its implementation last month illegal. The commission said the Legislature failed to follow proper procedure.

On Thursday, the Senate is scheduled to try again, voting on a concurrent resolution that says the job-banding rule is contrary to the intent of the constitution, as well as state statute.

The Assembly is set to vote Monday. If the resolution passes both Democratic-controlled houses, the commission would have 30 days to amend or withdraw the rules - or the Legislature could invalidate them by passing another resolution. It doesn't need approval from Christie, a Republican.

"We haven't done this before," said Sen. Robert M. Gordon (D., Bergen), who sponsored the resolution. "We really don't have a lot of experience with this."

Before the rule change, government jobs were structured by title (such as clerk), and advancement to a higher position in that title was based on examination or an outside review by the commission.

Managers had flexibility to choose among the top three candidates produced by that process. Candidates could appeal decisions to the commission.

Now, managers can promote employees without consulting exams or outside reviews, and job candidates who believe the selection process was unfair can appeal only to the head of the agency they work for, not the Civil Service Commission.

Critics of job-banding say it will eliminate the objective measure by which employees are promoted, giving way to a patronage system.

The Civil Service Commission says promotions will be based on competency evaluations. It notes that the judiciary has used job-banding for 15 years.

"Merit and fitness are at the core of this banding rule and thereby consistent with the constitution and statutes," Commission Chair Robert M. Czech said in a May 7 statement after adopting the rules.

The commission referred to Czech's past comments and declined to comment further.

The rules were proposed more than a year ago. The Legislature responded in December by declaring them inconsistent with legislative intent, and the commission amended the rules to apply only to state employees, not local ones. The rules also do not apply to public-safety employees like police and firefighters.

In January, the Legislature proceeded to invalidate the regulations. But the commission said lawmakers did not abide by procedure, arguing they did not consider or vote on the amended version.

The commission adopted the rules in May, even as the legislative leadership threatened to sue.