Title: Kain v. Dep’t of Envtl. Prot.

State: massachusetts

Issuer: Massachusetts Supreme Court

Document:

NOTICE:  All slip opinions and orders are subject to formal 
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SJC-11961 
 
ISABEL KAIN & others1  vs.  DEPARTMENT OF ENVIRONMENTAL 
PROTECTION. 
 
 
 
Suffolk.     January 8, 2016. - May 17, 2016. 
 
Present:  Gants, C.J., Spina, Cordy, Botsford, Duffly, Lenk, & 
Hines, JJ. 
 
 
Department of Environmental Protection.  Environment, Air 
pollution.  Regulation.  Administrative Law, Regulations.  
Declaratory Relief.  Statute, Construction. 
 
 
 
 
Civil action commenced in the Superior Court Department on 
August 12, 2014. 
 
 
The case was heard by Robert B. Gordon, J., on motions for 
judgment on the pleadings. 
 
 
The Supreme Judicial Court granted an application for 
direct appellate review. 
 
 
 
Jennifer K. Rushlow (Susan J. Kraham, of New York, & 
Veronica S. Eady with her) for Conservation Law Foundation & 
another. 
 
Jo Ann Shotwell Kaplan, Assistant Attorney General, for the 
defendant. 
 
Phelps Turner & C. Dylan Sanders, for Isabel Kain & others, 
were present but did not argue. 
                                                          
 
 
1 Shamus Miller, James Coakley, Olivia Gieger, Conservation 
Law Foundation, and Mass Energy Consumers Alliance. 
2 
 
 
The following submitted briefs for amici curiae: 
 
Stephanie R. Parker for Clean Water Action & others. 
 
Edward J. DeWitt for Association to Preserve Cape Cod. 
 
Arthur P. Kreiger & Jessica A. Wall for William R. Moomaw & 
others. 
 
Robert J. Muldoon, Jr., & Thomas Paul Gorman for David A. 
Wirth. 
 
 
 
CORDY, J.  In this case, we are asked to decide whether the 
Department of Environmental Protection (department) has 
fulfilled its statutory mandate under G. L. c. 21N, § 3 (d) 
(§ 3 [d]), which provides that the department "shall promulgate 
regulations establishing a desired level of declining annual 
aggregate emission limits for sources or categories of sources 
that emit greenhouse gas emissions."  By the terms of the 
enabling legislation, the Global Warming Solutions Act, St. 
2008, c. 298 (act), these regulations were to be issued by 
January 1, 2012, to take effect on January 1, 2013, and to 
expire on December 31, 2020.  See St. 2008, c. 298, § 16.  The 
department failed to take action by the statutory deadline, and 
in November, 2012, a group of residents submitted a rulemaking 
petition to the department seeking the issuance of regulations 
pursuant to § 3 (d) to limit greenhouse gas emissions2 in the 
Commonwealth. 
 
The department held a public hearing on June 13, 2013, to 
consider the petition.  Shortly thereafter, it issued a written 
                                                          
 
 
2 Unless otherwise indicated, we use the terms "emissions" 
to mean greenhouse gas emissions. 
3 
 
statement addressing the petitioners' concerns and concluding 
that it had complied with the requirements of the act, including 
those set forth in § 3 (d).  The statement also referenced 
specific regulatory schemes that the department had established 
to reduce greenhouse gases, including prescribed limits on 
sulfur hexafluoride leaks, a regional cap and trade market to 
manage carbon dioxide emissions known as the Regional Greenhouse 
Gas Initiative (RGGI), and a low emission vehicle (LEV) program 
aimed at reducing automobile emissions.  The department further 
stated that these initiatives, individually and in combination, 
fulfilled the mandate of § 3 (d).  No further action was taken 
by the department at that time. 
 
In August, 2014, the plaintiffs filed a complaint in the 
Superior Court seeking declaratory relief, or in the 
alternative, a writ of mandamus, on the grounds that the 
department had failed to fulfil its statutory mandate under 
§ 3 (d).  The parties agreed that their respective submissions 
to the court could be treated as cross-motions for judgment on 
the pleadings under Mass. R. Civ. P. 12 (c), 365 Mass. 754 
(1974).  The department again took the position that the sulfur 
hexafluoride, RGGI, and LEV regulations satisfy the mandate of 
§ 3 (d).  Following a hearing in March, 2015, the judge 
dismissed the plaintiffs' mandamus claim and entered judgment in 
the department's favor based on his findings that the three 
4 
 
regulatory initiatives cited by the department substantially 
complied with the requirements of § 3 (d).  The plaintiffs 
timely appealed, and we granted direct appellate review to 
determine whether the department has met its obligations under 
§ 3 (d). 
 
For the reasons discussed herein, we conclude that the 
unambiguous language of § 3 (d) requires the department to 
promulgate regulations that establish volumetric limits on 
multiple greenhouse gas emissions sources, expressed in carbon 
dioxide equivalents, and that such limits must decline on an 
annual basis.  We further conclude that the sulfur hexafluoride, 
RGGI, and LEV regulations fall short of complying with the 
requirements of § 3 (d), because they fail to ensure the type of 
mass-based reductions in greenhouse gases across the sources or 
categories of sources regulated under each of the programs, as 
intended by the Legislature.  Accordingly, we reverse the 
judgment of the Superior Court.3 
 
Discussion.  This case was decided in the Superior Court on 
the parties' cross motions for judgment on the pleadings.   See 
Mass. R. Civ. P. 12 (c).  For the purposes of this appeal, we 
                                                          
 
 
3 We acknowledge the amicus briefs submitted by the 
Association to Preserve Cape Cod; Clean Water Action, 
Environmental League of Massachusetts, Massachusetts Climate 
Action Network, Massachusetts Sierra Club, Mothers Out Front & 
others; Alternatives for Community and the Environment, the town 
of Duxbury, & Dr. William R. Moomaw; and David A. Wirth. 
5 
 
assume to be true the allegations in the plaintiffs' complaint 
and the exhibits attached thereto.  See Sliney v. Previte, 473 
Mass. 283, 284 (2015). 
 
The plaintiffs sought a declaratory judgment, or in the 
alternative, a writ of mandamus.  A party may seek a declaratory 
judgment "in any case in which an actual controversy has 
arisen."  G. L. c. 231A, § 1.  We interpret the "actual 
controversy" requirement generously.  See Gay & Lesbian 
Advocates & Defenders v. Attorney Gen., 436 Mass. 132, 134 
(2002).  "[A] dispute over an official interpretation of a 
statute constitutes a justiciable controversy for purposes of 
declaratory relief."  Santana v. Registrars of Voters of 
Worcester, 384 Mass. 487, 493 (1981), S.C., 390 Mass. 358 
(1983).  Declaratory judgment is appropriate here because the 
material facts are not disputed, and the plaintiffs challenge 
only the department's interpretation of  G. L. c. 21N, § 3 (d).4  
Moreover, we previously have recognized that "declaratory relief 
may sometimes be necessary to ensure that an agency will fulfil 
                                                          
 
 
4 The plaintiffs also requested a writ of mandamus to compel 
department to promulgate regulations that comply with G. L. 
c. 21N, § 3 (d) (§ 3 [d]).  Mandamus is an extraordinary remedy 
reserved for circumstances where the court must "prevent a 
failure of justice in instances where no other relief is 
available."  Service Employees Int'l Union, Local 509 v. 
Department of Mental Health, 469 Mass. 323, 334, n.11 (2014).  
Because declaratory relief is available in this case, mandamus 
relief is not appropriate. 
6 
 
its statutory mandate."  Smith v. Commissioner of Transitional 
Assistance, 431 Mass. 638, 651 (2000). 
 
1.  Statutory framework.  We begin with an overview of § 6 
of the act, which enacted the Climate Protection and Green 
Economy Act, G. L. c. 21N (statute).  The act was developed 
against the backdrop of an emerging consensus shared by a 
majority of the scientific community that climate change is 
attributable to increased emissions, as well as perceptions in 
the Commonwealth that national and international efforts to 
reduce those emissions are inadequate.  See Executive Office of 
Energy & Environmental Affairs, Massachusetts Clean Energy and 
Climate Plan for 2020 at 8 (Dec. 29, 2010); Executive Office of 
Energy & Environmental Affairs, Determination of Greenhouse Gas 
Emission Limit for 2020 at 1 (Dec. 28, 2010) (Secretary's 
Determination).  See also Massachusetts v. Environmental 
Protection Agency, 549 U.S. 497, 505 (2007) (petition by 
Massachusetts, with other States, local governments, and private 
organizations, arguing Environmental Protection Agency abdicated 
responsibility under Clean Air Act to regulate emissions of four 
greenhouse gases, including carbon dioxide).5  The act 
                                                          
 
 
5 See Environmental Protection Agency, Regulating Greenhouse 
Gas Emissions under the Clean Air Act, 73 Fed. Reg. 44,355 (Jul. 
30, 2008), in which the Administrator of the Environmental 
Protection Agency (EPA) stated that the "Clean Air Act, an 
outdated law originally enacted to control regional pollutants 
7 
 
established a comprehensive framework to address the effects of 
climate change in the Commonwealth by reducing emissions to 
levels that scientific evidence had suggested were needed to 
avoid the most damaging impacts of climate change.  Executive 
Office of Energy & Environmental Affairs, Commonwealth of 
Massachusetts Global Warming Solutions Act 5-Year Progress 
Report at 17 (Dec. 30, 2013) (Progress Report).  In accordance 
with these findings, the statute requires that, by 2050, 
greenhouse gas emissions be reduced by at least eighty per cent 
below 1990 levels.  G. L. c. 21N, § 3 (b). 
 
The same year that the act became law, the Legislature also 
enacted companion legislation concerning "Green Communities," 
St. 2008, c. 169; "Oceans," St. 2008, c. 114; "Clean Energy 
Biofuels," St. 2008, c. 206; and "Green Jobs," St. 2008, c. 307.  
"Each act addresses a separate but related piece of the clean 
energy economy."  See Report of the Senate Committee on Global 
Warming and Climate Change, No Time to Waste, at 10 (Feb. 13, 
2015).  The act and its companion statutes provide policymakers 
with a broad array of tools, including "targeted and technology-
specific policies[,] . . . economy-wide and market-based 
mechanisms," and renewable energy portfolio standards and energy 
efficiency improvements, to advance a clean energy economy while 
                                                                                                                                                                                           
that cause direct health effects, is ill-suited for the task of 
regulating global greenhouse gases." 
8 
 
reducing emissions and addressing the unique threats that 
climate change poses to the Commonwealth.  See Massachusetts 
Clean Energy and Climate Plan for 2020, supra, Executive Summary 
at 7. 
 
The act is one of the primary mechanisms for achieving 
reductions in emissions, and is the sole piece of legislation 
authorizing the establishment of legally binding limits on those 
emissions in the Commonwealth.6  Secretary's Determination at 1.  
The act represents a commitment by the Commonwealth "to the most 
ambitious greenhouse gas reductions for a single state in the 
entire country."  Progress Report at introductory letter from 
the Secretary.  To ensure that the Commonwealth remains on track 
to meet the reduction limit for 2050, the statute also includes 
timelines for achieving specified benchmarks in greenhouse gas 
reductions in 2020, 2030, and 2040.  G. L. c. 21N, § 3 (b). 
 
The act designates the Secretary of Energy and 
Environmental Affairs (secretary) and the department as the 
                                                          
 
 
6 By enacting the Global Warming Solutions Act (act), 
Massachusetts became one of three States in the United States to 
establish legally binding limits on Statewide greenhouse gas 
emissions.  See Executive Office of Energy & Environmental 
Affairs, Global Warming Solutions Act 5-Year Progress Report at 
17 (Dec. 30, 2013) (Progress Report).  In 2006, California's own 
Global Warning Solutions Act was signed into law.  See id. at 17 
n.5.  Massachusetts' act is based largely on California's 
version of the law.  Compare Cal. Health & Safety Code §§ 38500-
38599 (2014). 
 
9 
 
entities primarily responsible for implementing the act.7  See 
generally G. L. c. 21N.  The design of the act is synergistic, 
imposing numerous directives and timelines on the secretary and 
the department to perform certain duties, subject to deadlines.  
See St. 2008, c. 298, §§ 10-18.  These duties are to be 
performed chronologically, and are largely contingent on one 
another.  First, by January 1, 2009, the department was to 
establish a greenhouse gas reporting regime and registry, which 
permits the secretary to measure compliance with greenhouse gas 
emissions reduction efforts.  See G. L. c. 21N, § 2 (a)-(c); St. 
2008, c. 298, § 10.  Second, by July 1, 2009, the department was 
to determine a baseline emissions level equal to the sum of all 
emissions from Commonwealth sources for calendar year 1990 and 
"reasonably project" what the emissions level would be in 
calendar year 2020 "if no measures are imposed to lower 
emissions other than those formally adopted and implemented as 
of January 1, 2009" (known as business as usual level).  See 
G. L. c. 21N, § 3 (a); St. 2008, c. 298, § 14.  Next, the 
secretary was required, by January 1, 2011, in consultation with 
the department and the Department of Energy Resources, to a 
adopt Statewide emission limit for 2020 using the "business as 
                                                          
 
 
7 The Secretary of Energy and Environmental Affairs 
(secretary) oversees the Commonwealth's six environmental, 
natural resource, and energy regulatory agencies, including the 
Department of Environmental Protection (department).  See G. L. 
c. 21A, §§ 1, 7. 
10 
 
usual" baseline.8  See G. L. c. 21N, § 3 (b); St. 2008, c. 298, 
§ 15.  Additionally, by the same date, the secretary was 
required to adopt a limit for 2020 that was between ten and 
twenty-five per cent below the 1990 emissions level, as well as 
a plan for achieving said reduction.  See G. L. c. 21N, §§ 3 (b) 
(1), 4 (a); St. 2008, c. 298, § 15.  Next, by January 1, 2012, 
the department was to promulgate regulations pursuant to § 3 (d) 
"establishing a desired level of declining annual aggregate 
emission limits for sources or categories of sources that emit 
greenhouse gas emissions."9  See St. 2008, c. 298, § 16.  These 
regulations were to take effect on January 1, 2013.  Id. 
                                                          
 
 
8 As noted, G. L. c. 21N (statute) also requires the 
secretary to adopt interim emissions levels for 2030, 2040, and 
2050.  G. L. c. 21N, § 3 (b).  The emissions level for 2050 must 
be set at least eighty per cent below the 1990 baseline.  Id. 
 
 
9 A "[g]reenhouse gas emissions source" is any "source, or 
categories of sources, of greenhouse gas emissions with 
emissions that are at a level of significance, as determined by 
the secretary, that its participation in the program established 
under this chapter will enable the secretary to effectively 
reduce greenhouse gas emissions and monitor compliance with the 
[S]tatewide greenhouse gas emissions limit."  G. L. c. 21N, § 1. 
 
 
The department contends that the phrase "category of 
sources" is not defined in the statute.  To the contrary, the 
phrase "sources or category of sources" is part of the 
definition of "greenhouse gas emissions source" and plainly 
refers to a source of greenhouse gas emissions. 
 
 
"Sources or category of sources" is a term of art in 
environmental law, and refers to the process by which regulators 
sometimes devise categories or subcategories of sources to 
ensure that rules are implemented fairly and rationally as they 
apply to a regulated source of greenhouse gas emissions.  See, 
11 
 
 
It is undisputed by the parties that the department met 
each of the statutory deadlines, except for the deadline for 
promulgating the § 3 (d) regulations.  The department 
promulgated initial emission reporting regulations in December, 
2008, see 310 Code Mass. Regs. 7.71 (2013), and amended the 
reporting requirements of the regulations in June, 2009, to 
address reporting by sellers of retail electricity.  See 
Progress Report at 18.  In July, 2009, the department published 
a report establishing a 1990 baseline and projection of 
Statewide greenhouse gas emissions for a likely "business-as-
usual" case to 2020.  Id.  In December, 2010, the secretary set 
a Statewide limit on greenhouse gas emissions of twenty-five per 
cent below the 1990 levels by 2020.  Id.  See Secretary's 
Determination at 1.  At the same time, the secretary released 
the comprehensive Massachusetts Clean Energy and Climate Plan 
for 2020, discussed supra, in which he identified major sources 
of greenhouse gases that should be addressed as part of the plan 
                                                                                                                                                                                           
e.g., 42 U.S.C. § 7412(e)(2) (1999) ("In determining priorities 
for promulgating standards under subsection (d) of this section, 
the Administrator shall consider . . . (C) the efficiency of 
grouping categories or subcategories according to the pollutants 
emitted, or the processes or technologies used").  The EPA has 
often devised subcategories.  See, e.g., 61 Fed. Reg. 27132 (May 
30, 1996) (printing and publishing); 61 Fed. Reg. 46906 (Sept. 
5, 1996) (polymers and resins); 61 Fed. Reg. 48208 (Sept. 12, 
1996) (polymers and resins); 62 Fed. Reg. 49052 (Sept. 18, 1997) 
(steel pickling); 63 Fed. Reg. 18504 (April 15, 1998) (pulp and 
paper); 64 Fed. Reg. 27450 (May 20, 1999) (ferroalloys); 64 Fed. 
Reg. 57572 (Oct. 26, 1999) (publicly owned treatment works); 67 
Fed. Reg. 9156 (Feb. 27, 2002) (leather finishing). 
12 
 
to reduce emissions.  See Progress Report at 18.  The 
secretary's determination of the limit for 2020 was based on 
analysis by the staff of the agencies under the secretary's 
purview pursuant to the requirements of the statute, information 
and reports gathered from the Climate Protection and Green 
Economy Advisory Committee (established by the secretary), 
public hearings, and written public comments.  Secretary's 
Determination at 3-4.  His determination also took into account 
that actions taken under other statutory mandates were expected 
to produce Statewide greenhouse gas emissions reductions of 
about eighteen per cent below 1990 levels.  Id.  See Eastern 
Research Group Final Report to the Climate Protections & Green 
Economy Advisory Committee, Initial Estimates of Emissions 
Reductions from Existing Policies Related to Reducing Greenhouse 
Gas Emissions, 2, 4, 6 (April 30, 2010) (Final Report), 
available at 
http://www.mass.gov/eea/docs/dep/air/climate/ergrptf.pdf 
[https://perma.cc/8Q47-NGSA].  This eighteen per cent 
calculation accounted for reductions associated with the LEV 
program and the RGGI.  See Final Report at 2, 4, 6. 
 
Thus, to reach the twenty-five per cent reduction level by 
2020, the Commonwealth would have to implement additional 
measures to achieve approximately seven per cent in further 
emissions reductions.  The parties agree that these reductions 
13 
 
need not be attributable solely to regulations passed pursuant 
to § 3 (d), but rather recognize that a variety of policies and 
programs, including actions taken under other statutory 
programs, such as the Green Communities Act, G. L. c. 7, § 9A, 
may produce measurable reductions.  Secretary's Determination at 
5. 
 
2.  Statutory language.  General Laws c. 21N, § 3 (d), 
states that "[t]he department shall promulgate regulations 
establishing a desired level of declining annual aggregate 
emission limits for sources or categories of sources that emit 
greenhouse gas emissions."  The plaintiffs interpret the 
provision to require the promulgation of regulations that 
address multiple sources or categories of sources of emissions, 
impose a limit on emissions that may be released, limit the 
aggregate emissions released, set emission limits for each year, 
and set limits that decline on an annual basis.  They also claim 
that the regulatory initiatives cited by the department fail to 
comply with the requirements of § 3 (d).  The department 
counters that § 3 (d) requires it only to establish aspirational 
targets, or in the alternative, that it has substantially 
complied with the mandate of § 3 (d) through its promulgation of 
14 
 
the sulfur hexafluoride regulations and its amendments to the 
RGGI and LEV regulatory schemes.10 
 
We review de novo questions concerning the meaning of an 
agency's enabling statute.  See Commerce Ins. Co. v. 
Commissioner of Ins., 447 Mass. 478, 481 (2006).  Where the 
words in a statute are "clear and unambiguous," we them effect 
as "the legislature's expressed intent."  Providence & Worcester 
R.R. v. Energy Facilities Siting Board, 453 Mass. 135, 141 
(2009).  If we conclude, however, that the statutory language is 
"sufficiently ambiguous to support multiple, rational 
interpretations," Biogen IDEC MA, Inc. v. Treasurer & Receiver 
Gen., 454 Mass. 174, 186 (2009), then "we look to the cause of 
its enactment, the mischief or imperfection to be remedied and 
the main object to be accomplished, to the end that the purpose 
of its framers may be effectuated" (citations and quotations 
omitted).  Entergy Nuclear Generation Co. v. Department of 
Envt'l Protection, 459 Mass. 319, 329 (2011). 
 
The department has "a wide range of discretion in 
establishing the parameters of its authority pursuant to the 
                                                          
 
 
10 The department, in its brief, argues that § 3 (d) does 
not require the creation of entirely new regulatory programs, 
but rather that the department's amendments to existing programs 
can satisfy the mandate of § 3 (d).  We need not decide whether 
an agency can comply with a statutory mandate to promulgate 
regulations by referring to existing regulations, because we 
conclude that none of the programs cited to by the department 
complies with the requirements of § 3 (d). 
15 
 
enabling legislation."  Moot v. Department of Envt'l Protection, 
448 Mass. 340, 346 (2007), S.C., 456 Mass. 309 (2010), quoting 
Levy v. Board of Registration & Discipline in Med., 378 Mass. 
519, 525 (1979).   Nonetheless, statutory interpretation is 
ultimately the duty of the courts, and for that reason, the 
"principle of according weight to an agency's discretion . . . 
is one of deference, not abdication, and this court will not 
hesitate to overrule agency interpretations of statutes or rules 
when those interpretations are arbitrary or unreasonable" 
(citations and quotations omitted).  Moot, supra at 346. 
 
Moreover, our interpretation of statutes is not restricted 
to determining only their "simple, literal or strict verbal 
meaning" but also considers their "development, their 
progression through the legislative body, the history of the 
times, prior legislation, contemporary customs and conditions 
and the system of positive law of which they are part . . . ."  
Oxford v. Oxford Water Co., 391 Mass. 581, 588 (1984), quoting 
Commonwealth v. Welosky, 276 Mass. 398, 401 (1931), cert. 
denied, 284 U.S. 684 (1932). 
 
Taking these considerations together, we conclude that the 
language of § 3 (d) is unambiguous, and, as detailed throughout 
this opinion, we reject the department's interpretation of the 
provision, which would tend to undermine the act's central 
purpose of reducing emissions in the Commonwealth. 
16 
 
a.  Limits versus targets.  Because the question whether 
§ 3 (d) requires the department to promulgate regulations 
establishing binding limits on emissions or merely aspirational 
targets is central to our determination of whether the agency 
has met its obligations under the statute, we begin our 
construction of the provision with the meaning of the word 
"emission limits" as it appears in § 3 (d).  The plaintiffs 
contend that the phrase "emission limits" requires the 
department to issue regulations that establish binding caps on 
sources or categories of sources of emissions; the department 
argues that the phrase, as used in § 3 (d), requires it only to 
promulgate regulations that establish aspirational goals or 
unenforceable targets because the phrase is modified by the 
phrase "desired level." 
With respect to this point, we are guided by two well-
established principles of statutory construction.  First, where 
the same word is used in different parts of a statute, it 
"should be given the same meaning . . . barring some plain 
contrary indication."  CFM Buckley/North LLC v. Assessors of 
Greenfield, 453 Mass. 404, 408 (2009), quoting Connolly v. 
Division of Pub. Employee Retirement Admin., 415 Mass. 800, 802–
803 (1993).  Second, "[a]ll the words of a statute are to be 
given their ordinary and usual meaning" and we construe "each 
clause or phrase . . . with reference to every other clause or 
17 
 
phrase without giving undue emphasis to any one group of words, 
so that, if reasonably possible, all parts shall be construed as 
consistent with each other so as to form a harmonious enactment 
effectual to accomplish its manifest purpose."  Worcester v. 
College Hill Props., LLC, 465 Mass. 134, 139 (2013), quoting 
Selectmen of Topsfield v. State Racing Comm'n, 324 Mass. 309, 
312–313 (1949). 
Applying these canons of interpretation, the parties agree 
that the emissions reduction levels established by G. L. c. 21N, 
§§ 3 (b) and 4 (a), are legally binding "[g]reenhouse gas 
emission limits" as defined in § 1.11  See Secretary's 
Determination at 1.  Despite this, the department asserts that 
because § 3 (d) uses the term "emission limits" rather than the 
statutorily defined term "greenhouse gas emissions limit," that 
term is inapplicable to § 3 (d), and accordingly, regulations 
promulgated thereunder need not set binding caps on emissions.  
We disagree.  This argument ignores the fact that the term 
"emissions limit(s)," unmodified by "greenhouse gas," appears 
eight times in § 3 (b) and twice in § 4 (a).  In both of these 
sections, however, there can be no doubt that the "emissions" 
referenced are greenhouse gas emissions, and not emissions of 
                                                          
 
 
11 General Laws c. 21N, § 1, defines "[g]reenhouse gas 
emissions limit" as "an authorization, during a specified year, 
to emit up to a level of greenhouse gases specified by the 
secretary, expressed in tons of carbon dioxide equivalents." 
18 
 
some other type.  The same holds true for § 3 (d), which calls 
for emission limits on "sources or categories of sources that 
emit greenhouse gas emissions" (emphasis added).  It is apparent 
from the plain language that § 3 (d) refers to "greenhouse gas 
emissions limits" and that the term should accordingly be given 
its statutorily defined meaning, which calls for a volumetric 
cap on emissions, expressed in tons of carbon dioxide 
equivalents.12 
The context in which the word "limits" appears also is 
instructive to our determination of whether an actual cap on 
emissions is required by § 3 (d).  The statute directs the 
department to establish "desired level[s] of . . . emissions 
limits" through the promulgation of regulations.  G. L. c. 21N, 
§ 3 (d).  A regulation, by its definition, is not aspirational.  
See Black's Law Dictionary, 1475 (10th ed. 2014) (defining 
                                                          
 
 
12 Because we concluded that the term "emission limits" as 
it appears in § 3 (d) refers to the statutorily defined term 
greenhouse gas emissions limits, we reject the department's 
contention that the statutory requirement that limits be 
expressed in carbon dioxide equivalents applies only to 
"Statewide greenhouse gas emissions." G. L. c. 21N, § 1. This 
argument ignores the definition of "greenhouse gas emissions 
limit," which, by definition must also be expressed in carbon 
dioxide equivalents.  See note 11, supra. Moreover, the 
department offers no reason why it cannot express limits in 
carbon dioxide equivalents, which is how emissions reductions 
are measured and reported in reports related to progress in 
meeting the act's goals.  See, e.g., Executive Office of Energy 
& Environmental Affairs, Massachusetts Clean Energy and Climate 
Plan for 2020, Executive Summary at 6 (Dec. 29, 2010); Progress 
Report at 4, 12. 
19 
 
"regulation" as "[c]ontrol over something by rule or restriction 
. . .").  It is doubtful that the Legislature would require the 
promulgation of regulations had it only meant for the department 
to set aspirational targets, and if that was its intention, it 
could have used the word "target" or "goal."13  Given this, we 
see no indication that the Legislature intended to distinguish 
between the term "emission limits" in § 3 (d) and its meaning as 
defined in § 1 of the statute and as it is used in §§ 3 (b) and 
4 (a). 
 
Second, giving the word "desired" its ordinary meaning, we 
reject the department's position that the Legislature's use of 
the word evinces its intent for the department to establish 
target emissions levels rather than legally binding limits as 
inconsistent with the manifest purpose of the statute.  Although 
it is true that the word "desired" can mean "that is longed or 
hoped for," the term is also defined as "predetermined to be 
suitable or satisfactory; prescribed as requisite."  Webster's 
Third New International Dictionary 612 (2002).  Taking this 
definition together with the act's central aim of reducing 
emissions in the Commonwealth, as well as the language of G. L. 
                                                          
 
 
13 The Legislature also could have used the statutorily 
defined term "[e]missions reduction measures," which refers to 
"programs, measures, standards, and alternative compliance 
mechanisms authorized pursuant to this chapter, applicable to 
sources or categories of sources that are designed to reduce 
emissions of greenhouse gases." G. L. c. 21N, § 1. 
20 
 
c. 21N, §§ 3 and 4, it is apparent that the Legislature ascribed 
the latter meaning to the word "desired."  This interpretation 
accounts for the fact that the Legislature, at the time it 
enacted the statute, knew only that the emissions limit for 2020 
would be set between ten and twenty-five per cent below the 1990 
emissions level.  See G. L. c. 21N, §§ 3 (b), 4 (a).  Thus, by 
using the word "desired" to modify "level," the Legislature 
intended for the department to establish emission limits by 
sources or categories of sources, and left it to the department 
to determine what those limits would need to be to achieve the 
compulsory reductions set by the secretary in accord with 
§§ 3 (b) and 4 (a). 
 
The statutory deadline for promulgating regulations 
pursuant to § 3 (d) lends further support to our interpretation 
of the phrase "desired levels," especially in conjunction with 
the statutory timeline, which required the department to 
promulgate regulations after the creation of the greenhouse gas 
emissions registry, the determination of the limit for 2020, and 
the publication of the Secretary's plan for achieving the limit 
for 2020, all of which would need to be considered in 
determining both what sources of greenhouse gases to regulate, 
as well as what emissions limits would be required with respect 
21 
 
to those sources to achieve the reduction limit for 2020.14  A 
"clearer statement is difficult to imagine" (citations omitted).  
Attorney Gen. v. Commissioner of Ins., 450 Mass. 311, 319 
(2008).  We thus conclude that the plain language of the statute 
requires the department set actual limits for sources or 
categories of sources that emit greenhouse gases through the 
promulgation of regulations. 
 
b.  Remaining language.  We next examine the remaining 
language of § 3 (d) and what it means for the department to 
adopt "regulations establishing . . . declining annual aggregate 
emission limits for sources or categories of sources that emit 
greenhouse gas emissions."  G. L. c. 21, § 3 (d). 
 
The plaintiffs contend that the statute, by its terms, 
requires the department to promulgate regulations that address 
multiple sources or categories of sources of emissions, impose a 
limit on emissions that may be released, limit the aggregate 
emissions released from sources regulated by the department 
pursuant to § 3 (d), set emissions limits for each year and 
                                                          
 
 
14 The department also argues that the sunset provision 
associated with the § 3 (d) regulations supports its position 
that the Legislature did not intend for actual limits on 
emissions to be established under the provision.  A more 
sensible reading is that the sunset provision exists because 
after 2020, new annual limitations on emissions would have to be 
issued to ensure that Statewide limit for 2030, which has yet to 
be established, will be met.  In any event, the department's 
interpretation of the sunset provision as meaning it cannot set 
any limits under § 3 (d) would render the entire provision 
meaningless, and is therefore not entitled to deference. 
22 
 
establish limits that decline on an annual basis.  The 
department disagrees, and argues that § 3 (d) only addresses 
source-specific emissions and does not require the establishment 
of Statewide emission limits by source category, which would 
effectively limit the number of sources of greenhouse gases in 
the Commonwealth, and not just emissions from those sources.  
Although either approach might prove successful in reaching the 
Commonwealth's over-all reduction goal, our obligation is to 
determine which of these approaches the Legislature intended in 
enacting § 3 (d). 
 
We begin by observing that the words "regulations," 
"emission limits," and "sources or categories of sources" appear 
in their plural form in § 3 (d).  From this usage we may infer 
that the Legislature intended for the department to regulate 
multiple sources of greenhouse gas emissions.  See Leopoldstadt, 
Inc. v. Commissioner of Div. of Health Care Fin. & Policy, 436 
Mass. 80, 86-87 (2002) (court gives meaning to Legislature's 
affirmative use of singular or plural form).  We therefore 
reject the department's argument that each of the three 
regulatory schemes individually satisfies the mandate of 
§ 3 (d), as the plain language of the statute requires the 
regulation of multiple groups of sources.  The central purpose 
of the act is to effect significant reductions in emissions in 
the Commonwealth, and that purpose would be frustrated if the 
23 
 
department were to regulate emissions from only one group of 
sources or categories of sources.  We therefore conclude that 
the plain language of § 3 (d) requires the department to 
regulate not all, but multiple, sources that emit greenhouse 
gases. 
 
We next consider the meaning of the phrase "declining 
annual aggregate emission limits for sources or categories of 
sources."  The terms "emission limits" and "sources or 
categories of sources" derive from the definitional section of 
c. 21N.  Because the term "aggregate" is not defined in the 
statute, however, we look to its ordinary meaning:  "formed by 
the collection of units or particles into a body, mass, or 
amount: collective."  Webster's Third New International 
Dictionary 41 (2002). 
 
In this case, however, our interpretation hinges not on the 
literal meaning of the word aggregate, but on the word or phrase 
to which it applies.  Put differently, the question is whether 
the plural usage of "aggregate emission limits" modifies sources 
to be regulated, and requires that the emission limits imposed 
on specified sources of emissions decline on an annual basis, or 
whether, as the plaintiffs posit, it obliges the department to 
establish annual Statewide caps on emissions in the years 
leading up to 2020, which would result in the establishment of a 
set of declining annual "aggregate emission limits." 
24 
 
 
Here, the plain language of the statute supports the former 
interpretation, as there is nothing in the statutory language to 
indicate that the department must regulate every source of 
emissions in the Commonwealth.15  Indeed, plaintiffs acknowledge 
that the department has discretion to select what sources of 
emissions it will regulate pursuant to § 3 (d).16  Moreover, we 
are cognizant of the fact that not all reductions in emissions 
will be accomplished through the type of source-specific 
regulation called for by § 3 (d).  Taking these considerations 
together, it is evident that the phrase "aggregate emission 
limits" modifies "sources or categories of sources," and thus 
refers to the total mass of greenhouse gases emitted from each 
regulated group of sources or categories of sources.  Finally, 
it is apparent from the plain language of the statute that the 
                                                          
 
 
15 By its language, the statute accounts for the fact that 
not all sources of greenhouse gases require regulation to 
accomplish the Statewide reductions required by the statute.  
See note 9, supra. 
 
 
16 Although the department has discretion to choose which 
sources to regulate under § 3 (d), the plaintiffs argue that, 
even if the department's cited regulatory initiatives complied 
with the provision's requirements, the department must regulate 
a broader array of sources, and that it must do so through a 
transparent decision-making process.  Although we agree that 
regulations contemplated under § 3 (d) are subject to the 
requirements of the Administrative Procedure Act, G. L. c. 30A, 
nothing in this opinion should be construed as requiring the 
department to regulate a particular number of sources or type of 
source. 
25 
 
aggregate emission limits for each regulated source or category 
of sources must decline on an annual basis. 
 
Thus, we conclude that the plain language of § 3 (d) 
requires the department to promulgate regulations that address 
multiple sources or categories of sources of emissions, impose a 
limit on emissions that may be released, limit the aggregate 
emissions released from each group of regulated sources or 
categories of sources, set emissions limits for each year, and 
set limits that decline on an annual basis.  Moreover, by the 
design of the act, the department is well equipped to say what 
actual reductions in emissions sources and source categories can 
be achieved because it has already inventoried emissions from 
every source and source category of emissions in the 
Commonwealth pursuant to G. L. c. 21N, § 2. 
 
Our interpretation of § 3 (d) appreciates that, although 
the department and the secretary have considerable expertise in 
addressing the challenges that climate change poses to the 
Commonwealth, it is ultimately for the Legislature to make 
fundamental policy decisions.  The act makes plain that the 
Commonwealth must reduce emissions and, in doing so, may, in 
some instances, elevate environmental goals over other 
considerations.  Thus, contrary to the department's assertions, 
the Legislature's endorsement of a variety of emission reduction 
26 
 
strategies17 does not preclude our finding that § 3 (d) requires 
source-wide volumetric emissions limits.18  Moreover, such a 
policy choice is entirely rational in pursuit of the statutory 
goal of achieving legally mandated emissions reductions by 
                                                          
 
 
17 See, e.g., G. L. c. 21N, § 4 (b), which directs the 
secretary to 
 
"analyze the feasibility of measures to comply with 
the emissions limit established in subsection (a). 
Such measures shall include, but not be limited to, 
the electric generating facility aggregate limit 
established pursuant to [§] 12, direct emissions 
reduction measures from other sectors of the economy, 
alternative compliance mechanisms, market-based 
compliance mechanisms and potential monetary and 
nonmonetary incentives for sources and categories of 
sources that the secretary finds are necessary or 
desirable to facilitate the achievement of reductions 
of greenhouse gas emissions limits." 
 
 
18 Regulations issued pursuant to § 3 (d) may be 
characterized as prescriptive regulations, or what are sometimes 
called "command and control" regulations.  See EPA, National 
Center for Environmental Economics, Economic Incentives, 
available at 
https://yosemite.epa.gov/EE%5Cepa%5Ceed.nsf/webpages/EconomicInc
entives.html [https://perma.cc/NDD8-XMFW].  Prescriptive 
regulations typically mandate how much pollution an individual 
source is allowed to emit or what type of equipment must be used 
to meet such requirements.  EPA, Guidelines for Preparing 
Economic Analysis, Regulatory and Non-Regulatory Approaches to 
Pollution Control at 4-2 (Dec., 2010) (Pollution Control), 
https://yosemite.epa.gov/ee/epa/eerm.nsf/vwAN/EE-0568-
04.pdf/$file/EE-0568-04.pdf [https://perma.cc/RX73-YN3W].  The 
department points out that such regulations often use rates as a 
means of prescribing emissions limitations, and that § 3 (d) 
should be interpreted in this manner.  However, "[b]ecause a 
prescriptive standard is commonly defined in terms of an 
emissions rate, it does not directly control the aggregate 
emission level."  Pollution Control, supra.  Here, it is clear 
that the Legislature intended, through its unambiguous language, 
that the department issue prescriptive regulations that directly 
control emission levels. 
27 
 
2020.19  Where the Legislature has balanced public policy 
concerns and chosen a course of action, it is not for the court 
to second-guess its decision.  Wakefield Teachers Ass'n v. 
School Comm. of Wakefield, 431 Mass. 792, 802 (2000). 
 
3.  Regulatory programs.  Having concluded what § 3 (d) 
requires, we turn to the three regulatory initiatives cited by 
the department as satisfying the mandate of § 3 (d).  We begin 
by noting that the department does not dispute that it missed 
the January 1, 2012, statutory deadline for promulgating 
regulations pursuant to § 3 (d).  Moreover, based on our 
interpretation of § 3 (d) as requiring declining annual 
aggregate limits for regulated sources or categories sources of 
emissions, it is apparent that the regulatory schemes on which 
the department relies in this case do not comport with the 
requirements of § 3 (d). 
                                                          
 
 
19 See, e.g., Balmes, California's Cap-and-Trade Program, in 
Global Climate Change & Public Health, 383, 384 (Pinkerton & 
Rom, eds. 2014) (noting that direct regulations account for much 
larger proportion of emission reductions in California than 
reductions attributable to State's cap-and-trade system); 
Doremus & Hanemann, Of Babies and Bathwater: Why the Clean Air 
Act's Cooperative Federalism Framework Is Useful for Addressing 
Global Warming, 50 Ariz. L. Rev. 799, 799, 808 (2008) ("While 
[carbon] trading has a place in the policy portfolio needed to 
mitigate global warming, it alone will not be sufficient. . . . 
Therefore, a regulatory strategy that just caps emissions from 
electricity generating units -- such as the Regional Greenhouse 
Gas Initiative [RGGI] emission trading system in the 
northeastern states -- is unlikely to provide the scale of 
[greenhouse gas] reduction required to address the problem of 
global warming"). 
28 
 
 
a.  Sulfur hexafluoride regulations.  Sulfur hexafluoride 
is a "greenhouse gas" within the meaning of the act.20  G. L. 
c. 21N, § 1.  The purpose of the sulfur hexafluoride regulations 
is to achieve reductions in emissions.  310 Code Mass. Regs. 
§ 7.72(1) (2014).  The regulations took effect in 2015, see 310 
Code Mass. Regs. § 7.72(4), and proscribe excessive leakage of 
sulfur hexafluoride from electrical power systems that are 
insulated with this gas, known as gas-insulated switchgear 
(GIS).  Id. 
 
The sulfur hexafluoride regulations create a scheme in 
which maximum annual rates of allowable leakage for GIS in the 
Commonwealth decrease on an annual basis.  310 Code Mass. Regs. 
§ 7.72(1), (4).  The department has established a calendar of 
decreasing rate limits, beginning with a 3.5 per cent leakage 
rate allowed in 2015, and ending with a 1.0 per cent leakage 
rate allowed in 2020.  310 Code Mass. Regs. § 7.72(5).  Any GIS 
manufactured after 2015 must comply with the 2020 rate of 1.0.  
310 Code Mass. Regs. § 7.72(4).  The rates are calculated by 
dividing the total amount, in pounds, of sulfur hexafluoride gas 
leaked by a facility over the previous year by the total sulfur 
                                                          
 
 
20 The EPA describes fluorinated gases like sulfur 
hexafluoride as "the most potent and longest lasting type of 
greenhouse gases emitted by human activities."  See EPA, 
Overview of Greenhouse Gases, Emissions of Fluorinated Gases at 
1, available at 
http://www3.epa.gov/climatechange/ghgemissions/gases/fgases.html 
[https://perma.cc/NMN9-V9HT]. 
29 
 
hexafluoride gas capacity of all GIS in the facility.  310 Code 
Mass. Regs. § 7.72(6)(b)(8).  Failure to comply with the 
established rates is punishable by administrative penalties, 
including the imposition of a fine not to exceed $25,000 per 
violation.  See G. L. c. 21A, § 16; G. L. c. 111, § 142A. 
 
We agree with the plaintiffs that the imposition of 
declining rates falls short of complying with the requirement of 
§ 3 (d) that regulated sources are subject to a source-wide 
volumetric cap on emissions.21  A rate, by nature of being a 
ratio, is different from a limit, which sets a value that cannot 
be exceeded.  Because the sulfur hexafluoride regulations impose 
maximum rates as opposed to maximum limits on sulfur 
hexafluoride emissions, an emitter permissibly could increase 
its sulfur hexafluoride emissions by installing additional GIS.  
Thus, the regulations control only the rate of leakage 
                                                          
 
 
21 In support of the sulfur hexafluoride and LEV 
regulations, the department also contends that the statute, like 
the Federal Clean Air Act, equates "emissions limits" with 
"emissions limitations," permitting the expression of limits as 
"rates."  See 42 U.S.C. § 7602(k); G. L. c. 21N, § 1.  We reject 
this argument, as nothing in the language of the statute 
indicates that the Legislature intended to incorporate terms or 
definitions from the Clean Air Act.   Although G. L. c. 21N, § 7 
(d), uses the term "emissions limitation," it does so in the 
context of authorizing the Executive Office of Environmental 
Affairs to "enforce any rule, regulation, order, emissions 
limitation, emissions reduction measure or market-based 
compliance mechanism adopted by the executive office or the 
department pursuant to [the statute]."  Contrary to the 
department's assertions, this provision does not say anything 
about how emissions limits may be expressed. 
30 
 
permissible, and not the collective amount of sulfur 
hexafluoride emissions that leak from GIS in the Commonwealth in 
a given year.  Although these regulations will contribute to 
reductions in sulfur hexafluoride emissions, they cannot ensure 
the type of mass-based reductions contemplated by § 3 (d). 
 
The department argues that § 3 (d) does not require it to 
cap emissions levels by groups of sources, because doing so 
would effectively limit the number of sources of greenhouse 
gases in the Commonwealth, as well as emissions from those 
sources, rendering such regulations economically untenable, as 
they would prevent new or expanding sources of greenhouse gases 
from coming online.  To the contrary, the statute explicitly 
contemplates that new or expanding sources of emissions will 
come online in the Commonwealth.  See G. L. c. 21N, § 9 
("Nothing in this chapter shall preclude, prohibit or restrict 
the construction of a new facility or the expansion of an 
existing facility subject to regulation under this chapter, if 
all applicable requirements are met and the facility is in 
compliance with regulations adopted pursuant to [the statute]").  
To the extent that emissions limits may constrain new sources 
from coming online in the future, such a consequence is one of 
legislative making.  We note, however, that existing regulatory 
schemes provide frameworks for how regulations can address 
future emissions from new or expanding sources while ensuring 
31 
 
that over-all emissions limits decline.22  Indeed, the 
requirement of § 3 (d) that the aggregate mass of emissions from 
a regulated group of sources be capped allows for flexibility to 
create systems of allocation among sources within a category, in 
contrast with a scheme that mandates stipulated reductions at a 
discharge point, such as direct emissions reductions.  See G. L. 
c. 21N, § 1. 
 
b. RGGI and carbon dioxide budget trading program.  In 
accordance with G. L. c. 21A, § 22, department implemented a 
carbon dioxide budget trading program, which tracks the model 
rules of the RGGI and applies the RGGI standards in 
Massachusetts.  See 310 Code Mass. Regs. § 7.70.  The RGGI is a 
cap and trade program for electricity-generating facilities, 
such as power plants, that emit carbon dioxide, which is a 
greenhouse gas under the statute.  See G. L. c. 21A, § 22 (a); 
                                                          
 
 
22 See, e.g., the total maximum daily load program 
established under the Clean Water Act, 33 U.S.C. § 1313(a)(1) 
(2012); 40 C.F.R. § 130.2(i) (1989), which uses mechanisms such 
as a "reserve capacity" to account for anticipated future 
pollution.  "Offsets" provide another means of accounting for 
new or expanding sources of pollution, whereby future pollution 
from new or expanding sources of pollution is offset through 
mitigation measures.  See, e.g., 9 Va. Admin. Code § 25-820-70 
(2015) (requiring new or expanding facilities to offset 
increased total discharges of nitrogen and phosphorus in 
Chesapeake Bay).  The design of the RGGI also permits new or 
expanding sources of greenhouse gas emissions, as it applies to 
all power plants in participating States that exceed a twenty-
five megawatt capacity, whether existing or future. See Regional 
Greenhouse Gas Initiative, Inc., Fact Sheet, 
http://www.rggi.org/docs/Documents/RGGI_Fact_Sheet.pdf 
[https://perma.cc/S5Q6-DPZ7]. 
32 
 
G. L. c. 21N, § 1.  The RGGI established a market in which 
carbon dioxide emitters in the participating States can buy and 
sell a limited amount of emissions allowances.  See G. L. 
c. 21A, § 22 (b).  The program establishes a cap on the amount 
of carbon dioxide that power plants may emit by issuing a 
limited number of tradable carbon dioxide allowances.  See 
Regional Greenhouse Gas Initiative, Inc., Fact Sheet, 
http://www.rggi.org/docs/Documents/RGGI_Fact_Sheet.pdf 
[https://perma.cc/S5Q6-DPZ7] (Fact Sheet).  The number of 
allowances issued for the emission of carbon dioxide is 
determined by the maximum amount of carbon dioxide, measured in 
tons (the cap), among the nine States participating in the 
initiative.  Id.  The cap decreases by 2.5 per cent each year, 
through 2020.  Id. 
 
Massachusetts joined the RGGI in 2007.  See Regional 
Greenhouse Gas Initiative Inc., Program Design Archive, 
http://rggi.org/design/history [https://perma.cc/MP4Z-62HX].  
The Legislature subsequently required the department to adopt 
rules and regulations in compliance with the RGGI to "limit and 
reduce the total carbon dioxide emissions release by electric 
generating stations."  G. L. c. 21A, § 22 (b).  Accordingly, the 
department established the carbon dioxide budget trading 
program, which incorporates the RGGI scheme into its regulations 
and contains a schedule of the Commonwealth's annual "base 
33 
 
budget," which declines by the requisite 2.5 per cent each year, 
through 2020, when the base budget will be 12,617,227 tons of 
carbon dioxide.  See 310 Code Mass. Regs. § 7.70(1)(a), (5)(a) 
(2013); See Regional Greenhouse Gas Initiative Inc., The RGGI CO2 
Cap, available at http://rggi.org/design/overview/cap 
[https://perma.cc/T6V5-ATN6]. 
 
We conclude that although the RGGI program and amendments 
thereto are very important to the over-all regional scheme of 
reducing carbon dioxide emissions, they do not qualify as a 
regulation under § 3 (d).  The RGGI was established under G. L. 
c. 21A, § 22, a statute entirely separate from the act.  There 
can be little doubt that the Legislature, which directed the 
department to adopt RGGI regulations in G. L. c. 21A, § 22, knew 
of this preexisting statutory mandate when it enacted the act 
and § 3 (d).  Indeed, reductions from the RGGI regulation were 
accounted for in the eighteen per cent reduction in emissions 
anticipated under the "business as usual" projection calculated 
prior to the application of regulations under § 3 (d).  See 
Final Report at 2.  Moreover, G. L. c. 21N, § 3 (c), 
specifically carves out a separate process by which emissions 
levels and limits associated with the electric sector are 
established in consultation with the secretary and the 
Department of Energy Resources and are to take into account the 
34 
 
RGGI.23  By doing so, the Legislature recognized that a 
significant part of the electric sector would already be subject 
to regulations associated with the RGGI.  The RGGI is also 
addressed extensively in G. L. c. 21A, § 22, lending further 
support to the conclusion that the Legislature intended to treat 
emission reductions associated with the electric sector 
differently from other reductions in other sectors of the 
economy. 
 
The department asks us to read the statutory provisions 
together, as directing the department to promulgate regulations 
establishing "a desired level of declining annual aggregate 
emission limits," G. L. c. 21N, § 3 (d), and with respect to the 
electric sector, "tak[e RGGI] into account," G. L. c. 21N, § 3 
(c).  We disagree, as this reading ignores the Legislature's 
intent that regulations related to electric sector be treated 
differently from regulations promulgated under § 3 (d). 
 
Moreover, even if the Legislature intended for §§ 3 (c) and 
3 (d) to be construed together, the RGGI still falls short of 
complying with the requirements of § 3 (d) by virtue of the 
auction feature, which permits a regulated carbon dioxide source 
                                                          
 
 
23 General Laws c. 21N, § 3 (c), requires that "[e]missions 
levels and limits associated with the electric sector shall be 
established by the executive office and the department, in 
consultation with the department of energy resources, based on 
consumption and purchases of electricity from the regional 
electric grid, taking into account the regional greenhouse gas 
initiative and the renewable portfolio standard." 
35 
 
in one State to purchase allowances from any other State to meet 
the compliance requirements.  See Fact Sheet, supra.  Under the 
design of the program, if a Massachusetts power plant needed to 
purchase allowances at the quarterly RGGI auction in order to 
achieve compliance, and the allowances in the Massachusetts 
carbon dioxide base budget were exhausted, the Massachusetts 
power plant could purchase allowances from another participating 
State.  Because of this feature, there is no way to ensure mass-
based reductions in carbon dioxide emissions from power plants 
in the Commonwealth that participate in the RGGI.24  Thus, like 
the sulfur hexafluoride regulations, the RGGI may contribute to 
reductions in emissions, but does not comport with the specific 
requirements of § 3 (d).  Any other interpretation would 
diminish § 3 (d)'s purpose of achieving measurable and permanent 
reductions to emissions in the Commonwealth.25 
                                                          
 
 
24 Relying on data sets apparently generated from the EPA 
Air Markets Program Web site, the plaintiffs point out that 
greenhouse gas emissions from regulated entities in Rhode Island 
have increased under RGGI, exceeding the State budget and 
requiring the purchase of additional carbon dioxide allowances.  
EPA Air Markets Program data sets for carbon dioxide emissions 
under RGGI in Rhode Island in 2010 and 2011 show an increase in 
emissions by 87,609 short tons from 2009-2010 and 442,190 short 
tons from 2010-2011. 
 
 
25 Accordingly, we also reject the department's argument 
that regulations promulgated pursuant to § 3 (d) need not 
achieve greenhouse gas reductions specific to the Commonwealth, 
but may be regional in nature.  Not only is this argument 
inconsistent with the statute's central purpose of reducing 
emissions in the Commonwealth, but it also presumes the 
36 
 
 
c.  Low emission vehicle program.  The Federal Clean Air 
Act establishes motor vehicle emission standards. Under the 
statute, however, a State may obtain a waiver of Federal 
preemption permitting it to adopt California's more stringent 
emissions standards.  See 42 U.S.C. § § 7543, 7507.  In 1990, 
Massachusetts adopted California's standards for regulating 
motor vehicle greenhouse gas emissions.  See G. L. c. 111, 
§ 142K, inserted by St. 1990, c. 510, § 2.  That statute also 
required the department to establish and administer standards 
for motor vehicle emissions based on California's standards. 
G. L. c. 111, § 142K.  Pursuant to that statute, the department 
promulgated regulations incorporating California's LEV 
regulatory scheme.  See 310 Code Mass. Regs. § 7.40(1).  See 
Cal. Code Regs., tit. 13, § 1961.3.  The LEV regulations set 
exhaust and evaporative standards and regulate vehicle emissions 
on the basis of the fleet-wide averages of individual automobile 
manufacturers.  310 Code Mass. Regs. § 7.40. 
 
We conclude that the LEV regulations do not fully comply 
with the mandate of § 3 (d).  The original promulgation of these 
regulations significantly preceded the Legislature's adoption of 
the act.  Although amendments to programs such as the LEV 
program certainly advance environmental goals, they do not 
                                                                                                                                                                                           
department has authority to promulgate regulations that have 
force outside the Commonwealth.  Nothing in the language of the 
statute or of G. L. c. 21A purport to do so. 
37 
 
embody the change in "business as usual" required by the 
Legislative mandate in the act.26  Indeed, the fact that the 
Legislature was well aware of their existence and nonetheless 
directed the department to promulgate regulations in accord with 
new Statewide emissions limits is powerful evidence that neither 
the LEV nor the RGGI program, nor amendments thereto, satisfies 
the legislative intent of the act.  Although the LEV program has 
been amended since the adoption of the act, the amendments were 
made for the sole purpose of tracking exact changes to the 
California regulations after which it is modeled, see Cal. Code 
Regs., tit. 13, sec. 1961.3 (2014), which is required by the 
Clean Air Act.  See 42 U.S.C. §§ 7543, 7507.  It is highly 
                                                          
 
 
26 The department also argues that, where the term 
"regulations" is not defined in the act, the term should have 
its normal meaning as reflected in the Administrative Procedure 
Act, G. L. c. 30A, which defines the term "regulation" to mean 
"the whole or any part of every rule, regulation, standard or 
other requirement of general application and future effect, 
including the amendment or repeal thereof, adopted by an agency 
to implement or interpret the law enforced or administered by 
it."  G. L. c. 30A, § 1 (5).  Although we agree that this 
definition holds force, we reject the department's 
interpretation that the definition requires a conclusion that 
the LEV and RGGI programs and their amendments meet the 
requirements of § 3 (d).  Here, applying the literal 
interpretation of the definition of "regulations" would require 
us to ignore the over-all language and purpose of the statute, 
as well as the Legislature's clearly expressed intent.  We 
decline to interpret the meaning of regulation so strictly in 
this instance, where there is abundant support, in light of the 
language and purpose of the statute, for the conclusion that the 
Legislature intended for the department to regulate sources 
additional to those already subject to well-established 
regulatory schemes. 
38 
 
unlikely that the Legislature passed the act so that the 
department could promulgate regulations otherwise required by 
Federal law. 
 
These considerations aside, the LEV amendments fall short 
of the requirements of § 3 (d) because, like the sulfur 
hexafluoride regulations, the LEV program regulates through the 
imposition of rates, rather than actual caps on emissions.  The 
LEV regulations do not ensure reduced emissions, but instead 
established fixed rates of emissions from vehicles sold in 
Massachusetts.  Thus, although the rate may remain constant or 
even decline, the number of vehicles sold may increase.27  As a 
consequence, the LEV regulations may contribute to lower 
emissions from vehicles, but they cannot ensure that aggregate 
emissions do not increase.  Therefore, they do not comply with 
§ 3 (d). 
 
Conclusion.  Although the department's cited regulatory 
initiatives are important to the Commonwealth's overall scheme 
of reducing greenhouse gas emissions over time, they do not 
fulfil the specific requirements of § 3 (d).  The purpose of 
G. L. c. 21N is to attain actual, measurable, and permanent 
                                                          
 
 
27 The department seizes on this point to argue that the LEV 
regulations could only satisfy § 3 (d) if there were a cap on 
the number of motor vehicles sold in Massachusetts; however, the 
plaintiffs do not propose such a rule, and instead argue only 
that the LEV regulations do not meet the requirements of 
§ 3 (d). 
39 
 
emissions reductions in the Commonwealth, and the Legislature 
included § 3 (d) in the statute to ensure that legally mandated 
reductions are realized by the 2020 deadline.  Accordingly, we 
vacate the judgment of the Superior Court and remand the matter 
for entry of a judgment declaring that G. L. c. 21N, § 3 (d), 
requires the department to promulgate regulations that address 
multiple sources or categories of sources of greenhouse gas 
emissions, impose a limit on emissions that may be released, 
limit the aggregate emissions released from each group of 
regulated sources or categories of sources, set emission limits 
for each year, and set limits that decline on an annual basis. 
 
 
 
 
 
 
 
So ordered.