impact climate change. >> we will hear argument this morning in case 201530 west virginia versus the environmental protection agency and the consolidated cases. >> mr. chief justice, may it please the court in section 111 of the clean air act, congress directed epa to partner with the state to regulate a sourced specific level, which means identifying measures with -- measures particular buildings can take to reduce their own emissions. the d.c. circuit avp eight much -- gave the epa much broader power. power to reshape the nation's energy sector or any other industry for that matter just which sources to exist at all in setting standards to make it happen. no tools of statutory construction support that result. first, electricity generation is a pervasive and essential aspect of modern life and squarely within the states traditional. epa cannot regulate in ways that cost billions of dollars affects thousands of businesses and are designed to address issue with worldwide effect. this is a major policymaking power under any definition. and the responders argue epa can resolve these questions much clearly forbidden, goes back worthless congress authorized section 11 does not direct. congress is not done so here. second the words congress did use in the context replace them in section 111 traditional. together kate statutory terms, like the requirement standard before individual sources and focus on their performance so that congress did not greenlight the transformative power. and finally, stanek is no reason to avoid the merit pay were injured by a judgment that brings back to life a rule that hurts us and hits off the books or rules that benefit us. the argument their burden to show epa voluntary station and stay are not in the case they are not. we are asking for the classic appellate relief of doing undue with the court plugs at this court has full power to give it. the issues at stake confirm it should. in contrast, epa's important but environmentally focused role, congress and the state are able to weigh all of the competing factors and constituencies in play. the lower court was wrong to short-circuit the process here in the court should reverse pretty welcome the questions. >> you start your argument with a major questioned document. do you need that to win? >> we do not your honor. we think the text is clear the court can use any of the tools of statutory construction. i can focus on the particular words in context but major questions and the federal are also textual tools of construction of the court can and should use that as well precook so is the difference between clear statement and major question? >> so there are multiple versions of the clear statement candidacy questions is one of them the different version of the clearest statements. the clear statement part simply says what we assume would be in the statutes how clear congress would speak before courts are willing to find the agency power the major question is one version. >> what factors would be take -- taking into account to determine which approach we would use? >> i think it's important to look at what the constitutional norms in question are. cannons like major questions are grounded in separation of power if grounded in common sense presumptions about how legislators would operate we expect congress to put in the statues. when this court deals with major questions its focus on the nature of the power. here because there is transformative power that crosses industries and goes outside of epa core competency. this is the area where this court has been willing to apply the major questions before we argue it should do so here. >> i think i was just trying to get a little bit more specific. what is it about this case that suggests we should use one or the other? >> certainly. the power epa was claiming and the power plant is one example of that power. the power d.c. circuit gave it no further would be a new and transformative variety of agency power that is a major policy question. and so that is the sort of thing that courts are not willing to assume congress implicitly delegated those sort of questions. >> so does the statute, the text of a statute change of the because the problem is a big problem? >> no, your honor, the amount of the text of the statute change the clear statement is it looks at the words we would expect to be in the statue but certainly if the statute clearly allows this power. we are not asking the court to ignore that because we would say that actually satisfies the clear statement. >> thank you. >> i just want to follow up a little bit because i'm not quite clear what your position is. the major question stock you categorize a variety of the clear statement document question. >> it would, your honor, the major question doctrine is satisfied and there's a clear statement in the statute that congress in fact intended to give the power to the agency. >> some of the briefs talk about it, i don't know what with the right word is, informed by constitutional questions non- delegation or delegation. is that part of your submission or not? >> we have ordered non-delegation a constitutional canon. if it's right appropriately thought a delegation problem but we do recognize their significant overlap between major questions and nondelegation. they both get at the same constitutional norms of separation of powers about congress what it would not be presumed to delegate to an agency. non-delegation is asking different question of can congress delegate in hazard given sufficient guidance. major questions asked in the threshold question did congress delegate? here no matter what the issue is on nondelegation congress is not actually delegating. >> one problem that i have, is there is a word in the statute which i think is important. it talks about assistance. so epa has to have a system for existing plans. so, what is that system? i tend to agree with you that normally if you interpret the word system so that it totally 100% changes the opposites economic system of the united states it's hard to believe congress delegated that. but you want to jump from there to the idea it has to be plan by plan. now, at that point i think gee, it is easy for me too think of a system that they might choose epa that is not by plan by plan or within the fence. but, is not really a big deal. you want one? i mean it used to be years ago you had under the pjm system you have computers they still do they turn on. they turn on the electricity plants least cost or the cost of the day. so many companies put in time of day metering and so it is cheaper if you get your electricity at night. and so epa might say hey when you are doing that pjm, this is the computer for about 100 plans , when you do that add a sense to your presumed cost to reflect the fact is coal-based or subtract a cent it's lng-based and subtract two cents if it solar based. that is not a big deal. if you think 2 cents is a big deal let's make it a quarter. ok? and so there we are. i have something that's fairly minor, congress might well have delegated and it is not within the fence. so i got your basic point but it does not lead it seems to me your basic conclusion. >> if i can add to that point the source specific inside outside the fence shorthand that itself is not the major question here. that is the limit congress put in the statute. if you remove that limit, that is what shows how major the power at stake here is. because once that limit is gone, ep is not limited to something like two cents or quarter. >> not at all part you can use your system. what was the case i wrote all about it the court actually adopted it. look at the individual delegation. and you say well do we really believe on the basis of a number of factors not just whether it's a big deal, that congress would have delegated this power to this agency. this is what joses do, so let them do it. >> it is certainly true the justices of the court looks to major factors in the cases have looked at those. but again this is not simply the matter of a particular exercise agency power in this here for that is not how it's preceded look at the brown and williamson case for instance this court was faced with a particular tobacco marketing rule. but when determining whether it's a major question the court looked at how far the theory as statutory cases. >> i think what justice breyer is suggesting is that works against you rather than for you. in other words inside the fence reform to be very small or it can be catastrophic. inside the fence there are inside the fence technological fixes that could drive the entire coal industry out of business tomorrow. and outside the fence rule could be very small, or it could be very large. so the rule you are saying sort of emerges from the statute which is inside the fence outside the fence rule bears no necessary relationship to whether a rule is major in your sense of expensive, costly, destructive to the coal industry. it just bears no necessary relationship to that at all. >> your honor, i don't think that is true. there are limits congress put in the statute they make sense with the source specific. epa has the systems that are achievable we do it she removal admissions reductions that are adequately demonstrated those make sense for source specific requirement for they don't make sense epa regulated at a nationwide level. epa says we want to reduce coal plant significantly, of course i would always be achievable in the sense to reduce emissions for the actual limits congress written statutes don't make sense without all of the words congress put in which this is a statute that's focused on one particular source could do to make their own operations more environmentally efficient. >> council, i want to go back to a version of what justice keegan and justice breyer are asking which is, when i look at the epa as a whole, i see congress using very specific terminology. whether it's looking at an existing source, and technology for that source. a number of division says very clearly in existing source that has installed the best available control technology. that very much inside the fence. an existing source that has installed the best available technology. best in at least two provisions. but here, we have something much broader and very different words that say the best system. and does not use at the source, only for the state but not on the definition of what the epa has to do. so how do i give meaning to this -- those two different words? and then secondly, assuming that answer, massachusetts versus epa says that carbon dioxide is a pollutant under the clean air act. that's correct, right? >> that is correct. >> you are not challenging to question not challenging connecticut where it says congress clearly delegated to the epa the discretion about whether and how to regulate carbon dioxide, correct? >> we are not disputing the portion to whether and how per we are disputing how it means epa can do that. i understand what you are saying. this is really a step further than anything we have said before. all of our other cases, whether it is regulation of tobacco, or regulation of evictions under major questions doctrines have not addressed the how. now were going to the how. you want us to look at the how. justice kagan said inside the fence line requirements themselves can lead to generations shifting, because some of those could be so expensive that they fourth-generation shifting. -- force generations shifting. so if that's the case, how do we define this major question? it can't be that what congress has chosen might lead in or out the fence because there is some out of fence activities that don't necessarily lead to generation shifts system changing. biomass, which the rule precluded, requires certain plants to burn wood. and so that won't force generation shifting. so tease out for me more precisely what this major question doctrine involves? i cannot see it being in and out for the reasons justice kagan said and for the ones i just pointed to. so go back to two things, how do we give meaning to the different use of words in the statute, and to comment tease out for me what's a major question. >> certainly. thinking about how we look at giving meaning to those words? systems is a broad word we do not dispute that. this court always reads as a whole it does not look at isolated words and get them. in the decision which also interpreted the clean air act before is very clearly particular words meet a narrow work context focus interpretation. for look at the rest of the words in the statute before. >> there is a use limit there. it says best emission reduction. >> i don't read the word limit there. your honor, reduction is different than elimination bring out congress knows the difference between that because in section 112 right next to one 11th congress did use the term limited and prohibit this gives a different meaning to the word too. >> i wish there was regulations that would eliminate harmful carbon dioxide but even this one might eliminate it from some sources. but this regulation does not eliminate those admissions generally. >> a d.c. circuit interpretation of the statute does not give epa any place where it has to stop. it puts handcuffs on the clean power plant does not mean it is the next rule. >> it does give a place to stop. the statute says you have to consider costs and other various other factors. this is not a regulate to the end of the world kind of statute. it very clearly says there are other constraints that have to be considered to impose reasonable limits. >> i agree with you but if epa is looking at the grid wide level in dealing with an issue is massive climate change is hard to see would cause would not be justified much of the cost limit is not serving as a limiting factor if you take away the source specific limitations of the rest of the words in this statutes can clearly put. >> one argument we have not addressed yet and i want to make sure we do before your time expires is the question of standing. the general makes a strong argument that states are not harmed here because under the current state of affairs there is no rule in place and how could you be better off with the rule in place? >> can i that question? >> a relative article three question is whether the injury traceable to the judgment where the court can address that. the effect of the judgment is a clean power plant appeal is unwound so that rule could come back to life. that certainly enters the state -- injures the state even though nationwide the initial have largely been meant for the clean power plant 20 states and not met them there is no real question they're not injured. anything that happens after words temporary stay of voluntary cessation response is not met their heavy burden to show it's impossible to grant any relief at certain will not be harmed in the future. >> thank you, counsel. we will get to you in a moment. justice thomas, anything further? justice breyer? justice sotomayor? >> how is this any different than epa versus brown? they're the epa announced it was planning to modify regulation that have been challenged. the government asked like you are asking, that we offer guidance to the epa with various points in your brief you talk about guidance for the ruling that's taking effect. we strongly said that would be the advisory opinion. the government has disavowed and we said regulations coming, how are you different from the epa, number one. and number two, i am not sure how the ace rule which is also what has been put on hold but waiting for the new world. the new rule will supersede both. >> we do not know epa will do. >> that is absolutely true. >> that's the standard the court uses. with voluntary cessation the next rules entirely in the control of respondent, this court say the kate is not moot unless it's certain pre- this is not it moved question this is an advisory opinion question that is how the epa discussed the requests of course your honor that case will look towards the prudential factor think it's important to know it is your 15 for this court to rule on the merits of agency cases when rulemaking is ongoing even further in this case. we can look to the water's united states cases 2019 decision and national association of manufacturers. there the agency was even further along here, there been to proposed rules the court still seceded to give an answer on the merits. i think the potential factors are very similar here. that is another area where the administration agency was waffling on the decision evolved and the court found this was not a mootness question. they said the parties did not argument in good reason. i think the same prudential factors weigh strongly here. these are clean legal issues and the states need certainty. there is no jurisdictional bar the court has given the answer and there are very strong principles why it should. >> how does it change the advisory opinion? >> is not an advisory opinion because the court can still give us the relief of undoing the actual judgment. the clean power plan repeal would be final and the world would come back. your honor asked about how the a's will would help us? that is a will that is respectful of the limits congress wrote to the statute that is highly deferential. even if epa wrote later to change the world they would have to have additional burden of accounting for the factors that would lines to be harder for them to make change. they showed us to matter what epa may do at some point in the fact that the court can and should give us relief today based on the particular rule before us. >> justice kagan? >> you are responding to justice breyer's insistence that it is a broad rule saying there are other phrases in the statute that point to another way. i think you might have been interrupted, it might've been me. i think what you were going to say is the point of the phrase standard for performance of any existing source. is that right? >> that is surely one of them. >> the big one? >> we also think section 11181 has particular textual based as well. >> on the absence of you telling me what they are, the existing source applies to d1 and not one d1. that would suggest that a state even if it wished you could not do what this world does, is that right? >> we do agree the states are limited in setting the stage or performance of the same way the epa is limited when it sets emission reduction. >> isn't that sort of odd, this is supposed to be this cooperative federalist system and states are supposed to have a lot of flexibility and if the state decides this is what we want to do, we think it is not very costly, you are reading it too bad. >> there are two reasons why that is not a problem for federalism and state flexibility. states always retain inherent expression to state plans. if a state or group of states wants to have a training program they can do that. i think the second reason, it is a false argument to state more options for epa leads to more options for the state and the clean power plan shows that is true. it is an aggressive system with that said there were options for the state but there were not. it states could not have other options other than generation shifting and reduced but and the extremely aggressive measures epa set in place. this idea for getting epa more flexibility helps states is not true. it is important to give meaning to the actual tailoring congress put in 111d which of the states have the limitations from epa they're able to tailor that to particular sources based on remaining useful life and other sorts factors. that's written out of the statute anything as a system and apply at this level. >> can ask a different question. this major question doctrine, how big is a question have to be or how do you know when it is big enough? >> i think this court has certa