SAN FRANCISCO (CBS SF) — Two nurses’ unions filed federal charges against Sutter Health on Tuesday on behalf of nurses who participated in a one-day strike in September, a California Nurses Association spokesman said Wednesday.

The unions claim that Sutter’s hospital affiliates conducted an illegal lockout when they told striking nurses they could not return to work for five days following the strike.

The one-day strike on Sept. 22 involved an estimated 23,000 nurses from Sutter hospitals, Kaiser Permanente hospitals and Children’s Hospital in Oakland. Striking Sutter and Children’s Hospital nurses were not allowed to return to work for at least five days following the strike, while Kaiser nurses were allowed to return to work the next day.

Sutter officials have said this was because replacement nurses needed to be contracted for at least five days, according to terms set by nursing staffing agencies providing temporary replacements.

But the charges filed Tuesday with the National Labor Relations Board claim that since Kaiser nurses were able to return to work after only one day, it was not necessary for Sutter to contract replacement nurses for five days.

“They have yet to provide any compelling evidence to the public as to why they could claim to have justification for a lockout when Kaiser Permanente did not,” said Charles Idelson, a spokesman for the California Nurses Association.

Idelson said more nurses from Kaiser hospitals were on strike than from Sutter hospitals, further demonstrating that keeping nurses from work for five days was unnecessary.

Bill Gleeson, vice president of communications for Sutter health, said in a statement Wednesday that the five-day contracts were necessary to ensure continuity of care while the hospitals’ regular nurses were on strike.

“Our hospitals work to ensure continuity of quality care in part by contracting with firms to hire qualified registered nurses to fill in for those on strike. The hospitals do not dictate the terms of these contracts,” Gleeson said.

The charges, which Sutter officials said they have not yet seen, also allege that even nurses not scheduled to work on the day of the strike were required to report to work that day, or else they were considered on strike and unable to work for the following five days.

According to a statement on its website, Sutter notified nurses before the strike that they would be unable to work afterwards because of contracts with temporary staffing agencies. Announcements by the nurses’ union acknowledge that was a possibility.

Idelson said that there have been similar restrictions following strikes in Sutter hospitals in the past. “The fact that they’ve done it in the past does not make it any more warranted or appropriate or legal,” he said.

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