On the other hand, a study of 70 new school construction projects in Massachusetts from 1996 to 2002 concluded that after controlling several project characteristics, the ratio between GPs and the cost of school construction was not statistically significant. The study showed that GP projects were larger and more expensive than those that did not use GPs. The authors concluded that their statistical model may not fully cover the relationship between construction costs and APT21 If PTAs are more common for larger and more expensive projects, PLAs cannot increase construction costs. Instead, the size and costs of a project can lead a contractor to use a PLA to take advantage of the benefits it can offer. In 22 right-to-work states, collective agreements cannot require workers to join a union or pay union dues. In other countries, collective agreements may require workers to financially support a union as a condition of employment. Workers who do not join the union pay agency fees to the union. Union members are represented by the union but do not participate in union activities. Non-members may pay reduced agency fees if they object to the use of their payments for political activities. A PLA usually includes labour dispute resolution procedures. For example, if there is a disagreement between management and unions over the interpretation of the ALP, the dispute may go to mediation and then conciliation. THE AEPs generally contain a provision that unions do not agree on a strike and contractors agree not to block workers.

Another point of discussion is the proportion of trade unionists. Opponents say that after the PLA, business leaders must hire their workers through unions[66] and unionized workers are the majority of those working on PLA projects, although non-unionized workers make up the majority of construction workers. [56] Estimates of the proportion of non-unionists cited by PLA opponents are about 85%,[67] based on figures from the Us Department of Labor Bureau of Labor Statistics[68] and more recent data put the figure at 86.9%. [69] This figure is disputed by Denas, who indicates that the figures of opponents of the PLA are misleading and are based on census data that included an overly broad concept of a construction worker. [70] According to a 2010 Cornell University study cited by Mary Vogel, Executive Director of the Construction Institute, 60% of construction trades are unionized in Massachusetts. [71] Since its inception in 1998, The Construction Institute, a non-profit organization, has focused on the needs of the construction union sector in Massachusetts.