The Baltimore school system will deploy testing monitors to all schools administering the state assessments next week, even as the city principals union has called for investigations into alleged cheating at 16 schools to be suspended.

CEO Andrés Alonso has ordered steps over the past two years to prevent cheating scandals, this year spending about $360,000 on monitors. He also has taped a video message with stern warnings about the consequences of cheating, telling educators that it could be a career-ending move.

But educators have balked at how the system handles the investigations.

Jimmy Gittings, president of the principals union, has asked that the school board overhaul the process for investigating test irregularities and halt cheating probes at schools where 2011 scores plunged when testing security was heightened, pending the outcome of a legal battle with the school system. For six months, the union has been representing a principal whose school was identified for possible cheating.

Alonso ramped up efforts to ensure the city's test scores were clean after school officials confirmed three schools cheated on the Maryland School Assessments, dating back to 2008.

Testing has become even more of a focus as city teachers and administrators are evaluated partly on student achievement under new union contracts. And test scores help determine whether a school should be labeled "failing" under the federal No Child Left Behind act, though Maryland and other states have applied for a waiver from parts of the law.

Gittings said the administrative hearing under way for the city principal on whose behalf the union is fighting will prove the investigations are flawed and reveal underlying issues with the district's emphasis on test scores.

"Our attorneys feel very strongly and confident that when the hearing officer gives her opinion, it will be found that no violations took place," Gittings told the school board at a recent meeting. "And I am extremely sure and confident that the board will need to look very closely at negotiated contracts and pay-for-performance."

Alonso rejected his assertions, saying that it would be irresponsible of the system to not thoroughly investigate allegations, even if they are proved wrong.

"To say stop all investigations on the basis of the possible result in one case, when every case is different and we have found evidence of cheating in a school before, is to say look the other way," he said. "Every case is treated as unique, and we respond to the evidence presented in multiple forms of investigations."

Beginning March 12, every Maryland student in grades three through eight will be tested in reading and math for the MSAs. A group of roughly 200 retired educators and substitutes will be hired as temporary employees to observe and trouble shoot. Central office staff also will serve as testing coordinators, responsible for about five or six schools each.

Last year, the system sent monitors to every school. Until then, the system had only sent monitors into schools that had noted large gains and drops.

In the first year of the increased monitoring, the system experienced its first declines of Alonso's tenure, with 19 schools posting drops of 20 percentage-points or more. When the city's scores were released in the spring, Alonso said 12 schools were under investigation for irregularities; Gittings said that number has increased by four.

This year, school officials said the focus will be on proper administration of the test, rather than improprieties.

"Our main purpose this year is to make sure that when students take these assessments and when these results are reported, people believe them," said Jennifer Bell-Ellwanger, chief accountability officer for the school system.

In 2010, Alonso confirmed that George Washington Elementary, a school that had earned a prestigious Blue Ribbon designation and a visit from former first lady Laura Bush for its accomplishments, had cheated on the state assessments. An investigation found thousands of erasure marks on test booklets.

Last June, Alonso announced that two schools, Fort Worthington and Abbottston elementary schools, had cheated on the 2009 and 2010 assessments in an attempt to meet federal and district goals.

After Abbottston was monitored, pass rates plunged more than 50 percent in some cases, and officials said that many answers had been changed from wrong to right.

At Fort Worthington, test booklets were found to have been completed after a day's testing had ended, and the school also had tampered with its attendance data, a factor in making federally mandated goals.