Comptroller William Thompson is releasing his second education audit in two days right now, this time focusing on testing conditions and oversight in the city schools. Also for the second time in two days, the comptroller has barred a Department of Education spokesman from his announcement.

Today’s audit exposes “major flaws in testing by the New York City Department of Education,” Thompson’s office said in a press announcement this morning. But the audit says, “Our observations conducted at the sample schools on the day of testing did not reveal any instances of cheating.”

Today’s report is already drawing some of the same criticism from the city as yesterday’s audit, about how city schools qualify students for graduation. That audit found sloppy record-keeping at many city schools but no clear evidence of grade-tampering. City officials charged that Thompson conducted the graduation audit for political, rather than professional, reasons. As the city comptroller, Thompson’s job is to audit official city statistics. But he is also the main challenger to Mayor Bloomberg’s reelection bid.

DOE press chief David Cantor leveled the first complaints about today’s audit just minutes after the press conference began — a press conference that he was not attending after being kicked out by a member of Thompson’s staff. In an angry statement e-mailed minutes after he left the event, Cantor said his ejection shows that today’s audit was politically motivated.

“This is the first time i’ve ever been barred from entering a government press conference,” Cantor wrote. “If this was truly a non-political announcement, why in the world would they bar me or refuse even to hand me a copy of the audit from a pile two feet from the door?”

Thompson spokesman Jeff Simmons said the audit had been delivered to the department this morning.

Yesterday, Simmons barred a lower-level DOE press officer from the graduation rates press conference, saying that he was tired of having DOE flaks “shadow every move by the comptroller.”