1. Prohibited Conduct
To determine whether public employees are engaged in a strike or withholding services the CERB considers three factors:
- Whether the service is one which employees must perform as a condition of employment.
- Whether the service was in fact withheld or is about to be withheld.
- The party responsible for the withholding of the service.
1) Service as a Condition of Employment
Conditions of employment are defined as “not only those duties specifically mentioned in an existing or recently expired collective bargaining agreement (or personnel policies in effect for more than one year), but also those practices not unique to individual employees which are intrinsic to the position or which have been performed by employees as a group on a consistent basis over a sustained period of time.”
The CERB has also held the following regarding conditions of employment:
- The refusal to work overtime is not a strike where an existing collective bargaining agreement or past practice specifically authorizes the refusal.
- A concerted refusal to perform a task that is purely voluntary or within employees’ discretion is not a strike.
- An employee's failure or refusal to maintain a current professional certification required to perform employment duties may be a strike or unlawful withholding services.
- The expiration of a collective bargaining agreement specifying the reporting date for schoolteachers does not eliminate the teachers’ obligation to report to work on the first scheduled day of the school year.
- Where the employer has failed to consistently enforce a written requirement that employees perform a certain task or the manner in which they perform it, the failure to perform the task does not constitute unlawful withholding of services.
- Where the activity alleged by the employer to violate the Law consists of a reduction in employee productivity, the CERB does not necessarily infer from statistical data that employees are unlawfully withholding services, even if coupled with evidence that the employees were dissatisfied with the progress of negotiations.
2) Evidence of Withholding Services
Where there is no direct evidence of a strike, the CERB may make its findings based upon the available facts and the reasonable inferences drawn from them. Factors the CERB has considered in finding a strike include:
- The absence without excuse of virtually 100% of the employees in the context of a dispute over a collective bargaining agreement; and
- The fact that employees picketed outside their place of employment during work hours.
Other facts that may lead to an inference of a strike include:
- An abnormally high rate of absenteeism.
- The similarity of employee absence excuses.
- The timing of absenteeism coincides with expressed labor relations frustration.
Section 9A(a) also prohibits public employees or employee organizations from inducing, encouraging, or condoning a strike. Evidence of a violation includes:
- The failure of union officers to report to work.
- Union officials’ remarks indicating the existence of a strike vote by union members.
- Picketing by union officials during work hours.
- Information regarding the work action on the union’s website, including announcements or steps taken by the union’s executive board regarding an upcoming strike vote.
If an employer alleges that a union's parent or affiliate organization has also violated Section 9A(a), it must introduce sufficient facts to establish such involvement. In considering such cases, the CERB has held:
- An affiliated organization's representative on an informational picket line during non-work hours is alone insufficient evidence to warrant a conclusion that the affiliated organization was condoning or encouraging a subsequent strike. However, evidence of the representative's picketing during the strike may be sufficient.
- The mere presence of an affiliate's representative at bargaining sessions where local union officials indicate that a strike vote will be taken by the local membership is not sufficient to impose liability on the affiliate.
- Statements made by an affiliate’s representative do not amount to encouragement of a strike where the remarks referred only to an understanding that there arose a "spontaneous illness" among bargaining unit members.
- A union did not induce, encourage, or condone a strike where the union did not advocate on its website that employees call in sick (unlike another job action that union was advocating for at the same time), and union president told at least one other union official that he thought a sick-out was a “bad idea.”
The Supreme Judicial Court held that union officials have an affirmative duty to oppose a strike and to ensure union compliance with an injunction. The CERB has further found:
- The union’s participation in picketing or demonstrations, or the distribution of leaflets announcing the cancellation of a work day during a work stoppage or explaining the reasons for the work stoppage, is evidence of inducing and encouraging a strike.
- The union's establishment of a strike headquarters is evidence of a violation of the Law.
- The absence of a picket line or lack of a formal union endorsement of the strike does not shield the union from liability for condoning the alleged activity.
- The union is held responsible for the actions of its officers and leaders.
- A union's failure to present evidence to rebut evidence of its involvement, or to show that its officials took some affirmative steps to discourage unit members from striking, allows the CERB to draw an adverse inference of union inducement, encouragement, or condonation.
- The CERB may infer union inducement and condonation where the work stoppage was 90% effective, union officers failed to appear for work, and the strike started and stopped on cue, all of which occurred during a period of labor unrest.
- E-bulletins and articles in a union newspaper criticizing employer’s bargaining strategy and proposals, announcing executive board’s approval to take a motion to hold a strike vote before the membership, and other preparation for “exigencies” amply supported, “if not compelled” the CERB’s conclusion that the union unlawfully induced, encouraged and condoned a strike.
 City of Newton, 13 MLC 1462 (1987); City of Beverly, 3 MLC 1229 (1976); but see Town of Arlington, 3 MLC 1276 (1976) (where overtime is required by contract or is emergency in nature, concerted refusal to work such overtime may constitute a violation).
 Town of Danvers, 31 MLC 76 (2004) (CERB declined to infer that a strike was occurring from statistical data where evidence showed that officers were free to exercise their discretion whether to issue complaint citations, and there was no evidence that the town communicated to officers that they were expected to issue complaint citations within the 65% annual average).
 Hanover School Committee, 15 MLC 1182 (1988); Tewksbury School Committee, 12 MLC 1353 (1985); but see Shrewsbury School Committee, 26 MLC 103 (2000) (the absence of picketing by employees during work hours is not fatal to a showing that a strike is occurring).
 Shrewsbury School Committee, 26 MLC 103 (2000) (CERB concluded that a strike existed based on the fact that over 50% of workforce was absent and that the “Crisis Team” recommended that bargaining unit members report in sick); Boston School Committee, 14 MLC 1406 (1987); Wakefield Municipal Light Dept., 13 MLC 1521 (1987); Town of Abington, 12 MLC 1084 (1987) (100% of employees absent from same shift claiming illness); cf. King Phillip Regional School Committee, 37 MLC 81 (2010) (CERB declined to infer that there had been an unlawful withholding of services with respect to teachers writing letters of recommendation where there was no clear evidence that any teachers had actually stopped writing recommendations or spent less time on them, and no mutually understood practice as to the time teachers were expected to spend writing recommendations or their content); City of Medford, 11 MLC 1042 (1984) (where a small number of employees reported to work and signed out ill, and no additional evidence was introduced from which the CERB could infer that the illnesses were feigned, or that the absences were unusual in number, the CERB dismissed a strike investigation petition).
 Hanover School Committee, 15 MLC 1182 (1988); Northeast Metropolitan Regional Vocational School Committee, 13 MLC 1213 (1986); but see Quincy School Committee, 12 MLC 1675 (1986); City of Medford, 11 MLC 1107 (1984).
 Boston Teachers Union, Local 66, 33 MLC 133 (2001), aff’d sub nom. Commonwealth Employment Relations Board v. Boston Teachers Union, Local 66, 74 Mass. App. Ct. 500 (2009); University of Massachusetts, 28 MLC 91 (2001).
2. Work to Rule
Employees are engaged in a strike in violation of Section 9A(a) of the Law if they abstain in whole or in part from the performance of duties:
- Specifically mentioned in an existing or recently expired contract.
- That are not unique to individual employees because they are either intrinsic to the position or have been performed by employees as a group on a consistent basis over a substantial period of time.
When an employer fails to establish, communicate and/or enforce rules governing the duties that employees are obligated to perform, employees or unions who withhold, or urge or condone the withholding of those services have not engaged in an illegal work stoppage within the meaning of Section 9A(a). The CERB also held:
- The concerted withholding of services, which are not duties as so defined, is protected activity. A Section 9A(a) violation cannot be based on concerted conduct that would be permissible if done alone.
- Teachers’ refusal to teach summer school classes and attend professional development program at the end of the school year was not an unlawful strike because there was no express or implied contract between the school committee and the union requiring teachers to teach classes, there was no evidence that the school committee required teachers to teach these classes, and the duties were not intrinsic to the position.
- Police officers failing to issue traffic citations was not a strike where personnel manual made clear that issuing citations was within officer’s discretion and did not establish a quota.
- Graduate students’ refusal to turn grades in by noon on a specific day was not an unlawful withholding of services where, although various memos and the school calendar specified the noon deadline, evidence showed that graduate students had not met the deadline in the past without being disciplined, and other graduate students who were not participating in grade “embargo” also turned in grades late.
- Teachers’ alleged refusal to perform certain tasks, such as entering grades into grade database, writing recommendations, and teaching independent studies was not a violation where the evidence failed to show that teachers consistently used the grade database, were required to do so, or that they had stopped actually writing recommendations. Evidence also showed that teaching independent studies was a voluntary task that was not intrinsic to the position.
- Where the contract made clear that acceptance of on-call assignments was purely voluntary, the concerted refusal of housing inspectors to perform on-call assignments did not constitute an unlawful strike or withholding of services.
3. Threatened Strikes
Section 9A(b) permits a public employer to petition the CERB to investigate allegations that a strike is about to occur. In such cases:
- The CERB traditionally limited the application of this provision to situations where no further union action is necessary before a strike begins, e.g., when an actual strike vote has taken place.
- Where waiting for an actual strike vote to take place does not leave sufficient time for the employer to meaningfully engage the process set forth in Section 9A to prevent a strike from occurring, the CERB does not require a strike vote as a per se prerequisite to its finding that a strike is about to occur. Instead, it considers evidence short of an actual strike vote demonstrating that an actual threat of strike, work stoppage or slowdown exists. Such evidence has included the bargaining unit members’ unanimous approval of a motion approved by the union’s executive board to authorize a strike vote scheduled to take place five weeks later, the fact that the union’s bylaws contained a provision stating, “A general membership meeting is the only body which may accept or reject contracts or call a work stoppage,” and other evidence that the union was advocating and preparing for a strike.
- The CERB also takes into account whether the deprivation of services causes both financial and non-financial “irreparable harm” on the employer and its constituents.
- Where the evidence of a threatened strike was speculative, occurred several months before the petition was filed, and there was no evidence that the strike preparations had continued, the CERB dismissed the strike petition.
4. Remedial Orders
If the CERB concludes that a union has violated Section 9A(a), the CERB issues an interim order directing the end of the work stoppage. The following situations involve interim orders:
- The interim order may also address some of the issues underlying the work stoppage, especially where related prohibited practice charges are involved and require the parties to participate in bargaining, mediation, or fact-finding.
- The CERB has not excused an employer from continuing to negotiate because the union is on strike.
- The CERB lacks the authority to order binding arbitration of the dispute.
- The CERB also often requires a striking union to inform its members of the provisions of Section 9A(a) of the Law and of the contents of the interim order.
- The CERB may require the union to take necessary action to rescind and publicly disavow votes leading up to a strike vote.
- The CERB routinely retains jurisdiction to set further appropriate requirements.
- The CERB may retain jurisdiction to further investigate allegations against named respondents who were not served with notice of the investigation.
An unlawful work stoppage designed to affect the conduct of collective bargaining may also violate Section 10(b)(2) of the Law.
 Boston School Committee, 33 MLC 138 (2007), aff’d sub nom. Commonwealth Employment Relations Board v. Boston Teachers Union, Local 66, AFT, AFL-CIO, 74 Mass. App. Ct. 500 (2009); Peabody School Committee, 15 MLC 1147 (1988).
5. Constitutional Issues
Public employees have no constitutional right to strike. Specifically, the courts have held:
- An injunction that, among other things, ordered a union, its executive board, and its officers to disavow an executive board vote that scheduled a strike vote did not place a prior restraint upon the union to engage in public speech or debate, but rather prohibited it from engaging in actions that were properly prohibited under Section 9A of the Law.
- Even assuming that public employees have a constitutional right to strike notwithstanding the limitations set forth in Section 9A, the employees cannot exercise that right until they have followed the impasse procedures set forth in Section 9 of the Law, or on a showing that the imposition of those procedures would be unconstitutional under the circumstances.
 Commonwealth Employment Relations Board v. Boston Teachers Union, 74 Mass. App. Ct. 500 (2009).
 Id. (“To the extent that the conduct regulated by Section 9A includes both “speech” and “non-speech” elements, the purpose of the statute is entirely unrelated to the suppression of free expression. The CERB has a substantial interest in preventing a strike by the union members, and ‘[a]ny incidental limitation of First Amendment freedoms’ is justified.”)
 Labor Relations Commission v. Chelsea Teachers’ Union, Local 1340, 400 Mass. 120 (1987).
6. Employer Responses to Alleged Strike Activity
Section 9A(b) does not require a public employer to file a strike petition with the CERB in order to implement emergency measures to protect public services threatened by illegal job actions. As long as it acts in good faith, a public employer is permitted to take emergency actions to protect essential public services when those services are threatened, including locking out employees until the employer determines that it can operate its facilities securely. However, an employer seeking administrative or judicial relief from an illegal work stoppage must follow the procedures of Section 9A(b).
Section 15 of the Law prohibits public employers from compensating employees for any day, or part thereof, when the employees are engaged in a strike. Section 15 also permits the employer to invoke employee discipline and discharge proceedings without first petitioning the CERB under Section 9A(b) of the Law. The employer's action may be reviewed by the CERB in the context of a prohibited practice charge.
 Lenox School Committee, 7 MLC 1761 (1981), aff’d sub nom. Lenox Education Association v. Labor Relations Commission, 393 Mass. 276 (1984); School Committee of Leominster v. Labor Relations Commission, 21 Mass. App. Ct. 245 (1985).