granted your honor this case is about the government's request for a court order compelling routine business records held by a communications service from the lower courts denial of the government's application in this case was an error for two reasons first the government proceeded under the appropriate statutory framework and made the requisite factual showing under that statute and second there is no constitutional bart the government's compulsion of the records at issue in the application before the court that stick to the statute before we get to the constitution because obviously we're under an obligation to try to do that i have a lot of questions about the statute if i can ask from that outset first of all what's the difference between material stored for one hundred eighty days and material stored for less than that time i just don't understand the technical relevance your honor i believe is referring there's a distinction made in a separate part of the statute be some far reaching questions because i think that we have to figure out what congress thought it was doing and did so i go back to my question there are some power i'm things what's that what i understand you are to be getting at is why did congress draw that distinction in the place that it why do you choose one hundred eighty days yeah to the best of my understanding when congress enacted the underlying statute in one nine hundred eighty islip congress was grappling with at the time some very murky questions about whether or not the fourth amendment would protect certain kinds of information in the hands of a third party and certainly the legislative history in particular the senate and house reports  make clear that there was great uncertainty at the time the animating factor behind congress's inaccurate of the statute was to create statutory protection in the face of such constitutional is concerned about how much of a reasonable expectation of privacy attaches particularly if a customer of a communications service leaves information lying around for a long time in effect in the hands of a third party and so congress decided and the cell phone provider the e mail service provider the well that's what this is cell phone let's take the south from the cell phone provider so it has less privacy value if it's divined from the legislative history of from one nine hundred eighty six hungus was trying to draw what it thought were some reason distinctions between among different classes of information in the hands of a third party provider be that an e mail service provider be that a wireless communication service provider and for stored contents the contents of a communication congress decided and that somebody statute defined in section twenty five him contents that are in electronic storage for one hundred eighty days or less may be compelled by the government only person went to a warrant and there after that information may under the statute be compelled on a lesser showing understand subsection b i can explain to your honor why it was that congress chose that particular number one hundred eighty days i will suggest your honor it congress was mindful of the fact that it was unclear they certainly believe it was unclear whether or not fourth amendment protections attached to such stored content and so they extended protections to certain information content stored for let's call it six months or less and then lesser protection if such information was stored over the long haul by the service provider ok i hope that answers for this case though your honor of course deals with non contact information specifically the government's application in this case was made under section twenty seven zero three  case is not about the case is not about precise g p s data well but that isn't the whole point of this maybe we're getting that the government wants to get the out filing such an application and from that information it seemed to me that the government was interested in the identity is that right i mean we're not just talking about this case  passed that the government wants the identity it is that not right i mean they may have it in this case but in some cases they may not have it so isn't that right i think it s fact well the answer to you i think your honest question louis will vary from case to case there will be some cases where the government who has questionable differently when you make an application right under twenty seven or three d what has to be some kind of lead so i might it's usually telephone numbers or it might be a telephone number it could conversely be a person a subscriber's name asking if that particular person has the an address it could be a physical address if there is for instance you know a broadband internet service provider you'd like to know you know who is a registered customer of say comcast cable or that particular address not so it astrally says i'm looking at to know who the individual is i mean there may not be anything wrong with that i'm just trying to find out what the government is trying to get at with this that what with its interpretation of the statute and one of the things statute allows the government to compel any non content record all right so long as the government's able to identify you know what what the non contact content record could be for instance what are the what are the number was called right that's correct shell so you can trace you know who this person is in contact with indeed and in fact one of the classic illustrations of the use of the statute is if the government serves a grand jury subpoena on a telephone company whether that is a the standard your honor the test for the issuance of a grand jury subpoena is relevance and if i can respond presumably does to me not question the distinction between that and a pen register is it a pen register is prospected in effect it is an ongoing type of surveillance what's at issue here in section twenty seven or three is the government's attempt to compel disclosure of historical records records relating to some past periods opposed to you know the up if i can this field is growing as as we sit here making in from getting to know information so can we court when someone makes a nine one one call from a landline telephone the address that the first responders must go to is automatically transmitted to public safety answering point they know where to send the ambulance or the fire truck or the police that of course was a problem for wireless phones and in one nine hundred ninety six the f c c decided to issue what were produced enhanced nine one one or enon one one regulations because there was a problem if someone called for assistance using a wireless telephone and was unable to describe his or her precise whereabouts so could be disoriented senior could be a kidnapping victim locked in the trunk of a car there are various possibilities the first responders would have no idea how to respond and so in an attempt to respond to that public safety concern the f c c levied an obligation known as enhanced nine one one a's  one this was promulgated nine hundred ninety six made effective in one thousand nine hundred eighty and it required the carriers to be able to produce two through the network to the answering point nine one one operator  the cell location that's how our location was handling the particular call being made by the caller to the call center it didn't work out and the problem was because the information was so impre information the identity of the antenna and as we've set forth in our briefs these antennas are often divided into thirds so you have your twelve four forty eight and eight or twelve on the clock face you can get the area covered by one end and  those three hundred twenty degree areas that if all the you're on are and one head if that's all that the first responders receive it's not  before but i hope that the concern of the f c c of course was that that doesn't help you know against urban environment if all you know is that your emergency caller is somewhere within a three or four hundred yard radius yeah and even worse of course if you  be known as the phase two requirements which require when a user calls nine one one require that network to deliver much more precise location information better information that there are two ways and here is where i'm  temping has come back to judge the she must question the f c c gave the carers a choice of ways to implement that they could pick one of two technologies they could either do what's called handset solution which is essentially you put g p s in the phone  or the carrier could do what's known as network solution and that is what has come to be known in the vernacular is trying to elation where various measurements are made from the towers in proximity to the phone to calculate iraq position or the phone after house can they get well what the regulations require is fifty meters of precision or handset solution in two thirds of cases and it's actually for all cases ninety five percent it needs to be accurate within one hundred fifteen years for the network solution so what you have to shame is referred to as elation the parameters are one hundred meters or two thirds of cases and three hundred meters or ninety five percent but that is that's a class of information it's separate and apart from what the government has requested here and what's what can you get it statute permitted the respect of a part the government has asked for here does the statute permit the government to recruit up to request and according to the government to demand understand that but in addition the one hundred eighty day provisions of the statute relate to stuart content the information at issue here is not content to how long do they keep it that the information that we're talking about here this so called face s information they don't retain it at all in fact they generally do not receive it is it is not in the possession of the carrier what they do obtain and retain over time is t cell site information so the identity of the tower and where applicable the sector on the tower serving a particular communications to a so let me try to translate that so they know where the cell tower is and they can find out where the cell is within one hundred fifty meters right no you're on or not not going back the  only historical records and perhaps the best illustration of this if your honor i can refer the court to appendix page sixty three there is an exemplar of the type of record at issue in this p each line in this chart reflects a particular phone call so we see only understand that so each one shows in the last two columns are the key information years so we know how long the call was what time of day was in town up and the last two columns show in the next to last column what was the originating cell site in other words when this whole started what was the tower and if that was a multi phase tower which face on the tower was handling that call it doesn't tell us where the phone and those are not phone cord and that's just the name of a tower is located somewhere on the ground fargas the tower have to be asking how close it does this does not reveal distance in from out as a matter of physical whatever we're talking about how close can the government  where some of their people are or have been for example have been and what may be happening today in iran have been at a protest or and i meeting or add a political meeting now can the government assure us that one it will never try to find out that information and to whether that information would not be of it would not be hovered by d your honor i can't speak to future hypotheticals to what might happen but then we have to be concerned about that if the statute would permit the government this government right now but a government to get information as to where and it doesn't have a g p s but this could be instead of a g p s wouldn't the government a government find it useful if it could get cause because it's relevant that's what i mean the current you your papers admit that the shallowing that needs to be made for a subsection  less than the showing that needs to be made for a warrant that's correct or ok so the question is candied be used for that  it can be used constitutionally for that purpose and the reason i understand your honour's concern about this is future cases those hypotheticals but i think it is clear under the supreme court's case law that fourth amendment issues must be measured on the basis of the facts before the court and i'm not talking with what i've set aside the constitution my concern i know i can't offer much to shimla but if we can decide this problem here is that magistrate judge lent to him had before her no actual factual record measure judge lenihan did not solicit and therefore did not receive any briefing whatsoever from the government on the nature of the what you see there is all the location information that we may be moved back to where you were several minutes ago but as far as this application is concerned then is it your position that in correct your honor now but you know better than that now is this true how close or how closely a cell phone user can be cracked on the basis of this kind of information depends partly on on the location in other words in certain areas cell phone towers are much more situated much more closely together so you know to move from one cell tower to another is a much shorter distance so you can place a person you know closer to the tower than where the towers are more far apart that is that true as a general proposition your are it is true that the towers are much more closely spaced in dense urban areas such as manhattan and outfit i'm sorry what philadelphia or philadelphia absolutely in any in any densely populated urban area because there are more callers there's more need for network capacity downtown and everyone is on his phone making a call the next person who takes his call to place a call is not going to be able to talk through the tower that is nearest to him he may be bumped over to the next hour that's five hundred yards so even though you can't correct the cell phone to closer than say within hours with a couple hundred yards of cell towers you can get a general track at y i mean you know somebody say you know going from washington d c to philadelphia right if the person is again to look to historical records that would be true if the person were constantly making and receiving phone calls if your honor takes a look at the penny reach sixty three that same example are you see these are not records from every seven seconds or every seven minutes the records relate solely to actual communications occurring through the phone so when the phone call starts and when the phone call ends but if the phone is not in use if the phone may be on but the records are not generated we cannot right and they can get their hearers for thirty three on the same day for thirty nine pm on the same game four forty on the same day that's pretty  honor the calling records the numbers that are being called or from whom calls are being received by the same user we can compel those with a subpoena that's right that's right and as i write this you can a lot of the information but it looks to me like you want to maybe even in this case you could have gotten with the warrant and i don't understand i am think the magistrate judges i've been on this but for thirty years more than thirty years the magistrate judges that i have seen are not very grudging about granting warrants if you could have gotten a probable cause warrant why do you want to make the point that you don't have to show have a book with us well it's interesting your honor because the rationale that was adopted in this case by the lower court wouldn't limit the the reviewing court record to him yeah patients presented to demanding probably cause under the rationale that was articulated below the court could demand proof by a preponderance of the evidence judge lana hands opinion says that it's up to the court to decide in effect what showing could be made so that you know it bests the trial court the magistrate judge with what's essentially unlimited discretion to decide what showing should be statute and what is in some ways unique about the store communications act is that there is a range of compulsory mechanisms set forth in the statute that the government may use or is required to use depending upon the particular kind of customer records that are sought to be obtained so we see for instance in section twenty seven or three c to f a list of things the government can  has a court order for disclosure may be issued by any court of competent jurisdiction and shall issue only if the government or first the following it doesn't also explicitly mentioned infection twenty seven if we see one a one of the other mechanisms by which the government may compel non content records is a warrant using the procedure described in the federal rules of criminal procedure demanding a warrant the congress has set out a separate mechanism that intermediate standard that does not require a showing of a will cause and so in order to prevent subsection v from becoming an all of the the court i believe has to understand that congress has made a decision that the judge does not have the action to demand more here's a separate provision where the government can show probable cause in pain a warrant i talking about c i understand your honor but he would be the same warrant if i may give you are an example suppose an investigator is investigating use of a particular yahoo email account and the investigator wants to obtain the stored contents of the email that possession of the service provider yahoo but also wants to obtain friends actual information or subscriber information to the user is how they pay for the service how long it had to service and so on a single warrant the disclosure of all of that information and that is why section twenty seven if you see one apr non content is there if that weren't there the government have to get a warrant for the content and come up with some other piece of are that is the government's understanding of why congress structured the statute in this way the government yeah you have any legislative history so your honor i be happy to provide some supplemental briefing to the court and what will we have enough briefing right now electronic or wire the answer here is neither your honor this is information about the communication a telephone call is a wire communication but what's at issue here is not the contents of what's happening in the telephone call at issue here is very similar to the numbers dial to place the telephone call it's it's auxiliary information it's information about but it's not the substance of the communication itself now it's a telephone i didn't mean to imply otherwise ron congress created again if i if i can just step yeah i think i'll try not to make a full page of history this time or are both in the  then we have wire and electronic and the key distinction between those two terms as they are defined in section twenty five ten is a wire communication necessarily involves  involves the human ports so to boil that down very simply a if phone call or two people are talking to each other that would be the classic instance of a wire communication and electronic communication is all those other kinds of communications e mail pager messages and so on it does not involve the human voice but which traverses some sort of interstate network or at least a network with an interstate nexus argue in support of the lower court's holding the fourth minute text cell phone location information requires the warrant have the government to obtain a search warrant for acquiring it as well as in support of the stored communications act gives judges the amendment but hope to focus primarily on the statute them because it's how we construe the statute that will define whether the court must address or can avoid the constitutional issues i want to address and question that came from the bench earlier i think you were right your honor to focus early on on the breath of the types of data that can be obtained under twenty seven zero three d essentially any record that a communications provider has on a subscriber customer can be obtained under twenty seven zero three d and that includes not only the single tower data shown in the exemplar that it's power and sector data but  data or as you pointed out email and i think g p s is important in this case as the submission we made showed in the model application the government believes it could have pain g p s data under twenty seven zero three d and so for that reason we think that quibbles over our accuracy in this case are a bit of a red herring because how the court construe the statute here is going to define how it's applied in law don't you just a minute don't you think  rule on g p s and all these things that are not part of this application and we're asking for an advisory opinion i should absolutely not your honor with respect we are actually counseling that as part of the doctrine of constitutional avoidance you need to consider the impact of your ruling on future cases so to the extent if you were to rule that twenty seven or three d did not give courts the discretion to require a warrant that would apply in another case where the government is seeking highly accurate you know but suppose suppose we said well you know in this case it seems to be ok because it's not that precise but we're telling the government now discretion to require a warrant well i know it but the reason you're saying we should because it in walls things like you know b s them very well to be clear you think that the data at issue in this case is accurate enough to implicate the fourth or the thought about that now you see the government said their position well the closer you can really get as you know within a couple hundred yards right you just move as a matter of fact we do your honor how close you think you know this kind of information can you know is it as a general proposition well your honor looking at the record there is actually nothing in the record that defines the upper limit of the position of th state the closest that we have the best example that we have is the testimony of the f b i his own cell location expert agent shoot in a local bank robbery case and the government quotes part of that in its own brief at page seven where agent shoots specifies looking at the sack same type of data from the same carrier in this case he was able to pinpoint a suspect to a particular block the thirteen hundred block of west day high ave here in philadelphia looking i and i hope the court made picture additional notice upon looking at a map i went online and looked at several maps of the area that's point one mile that's five hundred twenty feet so that is fairly accurate data and even so we still don't know how much more precise it might be and that is why we are getting our briefing argue here that if you believe that the question of accuracy is truly critical to deciding this question that  location tracking presidents of kero in knots there's been a myth fostered by the governments discussion of those cases that the beepers there were very precise but they were not they were very crude it was  you whether you were getting hot or cold whether you getting closer to the beeper or not it didn't specify well the beeper is in that direction forty feet away therefore you know it's in the house rather using that crude information the government in d the location of the beeper inside of private spaces justice scalia make specific reference to this in his college decision where he discusses why the fact that the government is inferring facts about the inside of the home doesn't insulate the government does routinely use this type of information to place people in at and in particular at resident at a place but not you know they don't try to find out what's going on inside the home well to be except maybe except maybe make a cell phone call under under kero in knots the supreme court wasn't looking for whether the beeper revealed the movements of the item in the hole it was looking to see whether the beeper was used to confirm that the article was in fact in the home which is a fact about the interior of the home that the government otherwise would not have known but for a physical search it so there's no need to be able to track a phone within a house only to track it to a house and indeed it is not necessary to be able to track it and pinpoint it within the house but rather simply information allowing the government to infer that the phone is in the house is sufficient as again as as as justice explained kero in the case but i think there's another a good example i mean essentially the government is trying to say that under the care of case general vicinity information is not protected but that was not the rule  was does the while the question was does surveillance that reveals information that could not have been viewed from public surveillance is that tread upon the fourth member the answer was yes and i can  of privacy and that is facts about the location of their phone even when it has been withdrawn from public and we believe that under kero those facts are protected by the fourth amendment however i also elucidate a bit on the rule in kero about if it was not visible from public surveillance it's protected a simple hypothetical will demonstrate how even if the cell phone data is very imprecise it will reveal makes a call from the office they confirm that he he's got to solve you then puts the cell phone in his pocket walks home and then makes a call it home from that fact they can infer that the phone is in his home however that fact was never revealed the a visual surveillance and could not have been revealed the a visual surveillance and therefore the government has learned that the phone is in the house something it could not otherwise have learned but unless it had done a physical search under care i think this is clear that that this that this would violate the fourth minute without a search warrant but if i may your honor go back to the statute and it's worth it says that a court order may be issued by any court that's a court of competent jurisdiction and shall issue only if the government offers specific in our particular bill facts skipping over the standard of it  i think the key language there is the shall issue only i think it's worth noting that the phrase about jurisdiction may be issued by any court was not in the original nine hundred eighty six act but was added in held and as the third circuit itself has recently held recently in town ships of finnick on which was one of our twenty eight day authorities only if has a specific meaning it mean it identifies a necessary but not necessarily sufficient condition meaning that the government has to make this showing to get to your butt that the court doesn't have to grant the order if it makes this trial any other standard and it's hard for me to see when they have this phrase in here about you know what showing is necessary in this statute to read just that it is giving giving the magistrate sort of order it's not discretion to say well if you want to be order then you need to give me this it's either to grant or to not invite denying require the government to instead seek a probable cause war that discretion is of course bound by abuse of discretion the court cannot abused its discretion and deny an order because it got up on the wrong side of the bat or doesn't like the prosecutor or anything like that in terms of the standard if the if the option is either of you order or if denied a warrant under rule forty one rule forty one specifies that if the government makes a probable cause showing the court must issue the warrant and so so the government's fear that courts will willy nilly be throwing around all kinds of new standards is simply not the case and not supported by the statute the question is does the court have the discretion to deny it the order even if the showing is made and instead require a war phone should be considered a tracking device  records at issue here are records pertaining to a subscriber customer of electronic communication service and therefore fall within the ambit of the stored information regardless of whether a cell phone is considered a tracking no your honor again that the well so that discussion goes to one that's from the so that is from the government's argument where they disagree with judge lend a hand as do we as to whether or not this data is actually covered by the stored communications that we agree with the government that it is that is covered by this in our communications and that is one point of agreement that we honor the only has to have some meaning or else you are plus the government proposes one reading which is well without the only then the government could issue of the order on specific articulable facts or it could issue it on a lesser showing but this is an absurd reading if you compare the other surveillance that you which all use if rather than only if the government's reading of what only means were correct then a court could issue a warrant under rule forty one without probable cause it could issue an order for a pen register and of the pen register statute without the required  issue a wiretap order under the wire taps at you without without probable cause as required by that statute and this is clearly not the case and so the only reading of the statute only meaning is what we call the permissive reading the one that gives the court discretion as opposed to the government's mandatory there are some statute protected the statute does not specifically carve out any particular types of records as being unobtainable under the plain language of the statute any record pertaining to a subscriber customer of an electronic communication service is a pain of all and that's why we continue to try and focus the court's attention on the facts of these other more precise types of records such as because if you accept the government's mandatory reading then the court will have to issue the orders twenty seven three the orders on the specific unmarketable back showing no matter what type of record is at issue and so even if you don't think we do believe even if you don't think that the record at issue here implicates the fourth amendment under carolynn they are certainly more accurate data such as g p s and yet that data would be equally obtainable under this statute as demonstrated by the fact that the government's model application includes g p s as one of the things sought under a deal morning your honor to me please the court i'm susan pre law professor at the university of san francisco school of law women and i guess this case presents a fourth amendment issue of first impression about the government use of a truly novel technology that can invade the privacy of all americans who carry cell phones in their pockets and purses when the government acquires historical so location information that effectively commandeers our cell phone and turns them into electronic trackers that report without our knowledge or consent where we have been and how long we have spent there we should be able to use our cell phones without them creating a virtual map of our every movement an that's a complicated question in the sense that it depends on what records are available to the government and there are many cases in which the government has asked for much more detailed information than just information at the  in addition it's not clear exactly what information we furnished to the government in response to whatever their application or imagine it to your knowledge do cell phone providers routinely  information you're on our cell phone providers do not want to reveal where you are using you don't know i don't know what they store i do know that they have but they are able to collect that information i do know that they or you don't know to what extent that information is available to the government under the stored communication that you don't know whether it's or i do know that they collect the information because the government has requested that amy collect it routinely for every cell phone user it you know every seven seconds again your honor i know the government has to that has to be no i don't i don't see why they would collect and store that information i would hope they wouldn't get to that point i was certainly they would hope that but as you know storage storage costs have got gone down incredibly all the time so it's it appears from from the exemplar that cell phone companies retain databases of whatever information is needed in fact in the case involving the judge borenstein case out of new york the court said that the provider was providing raw data to the government that they in turn could put into a spreadsheet and the case out of texas the government asked for multi tasker information that included signaling data the angle and strength and timing of the signal another court has pointed out that the difference between and as well as magistrate as lenahan that the difference between historical data and perspective it is rather arbitrary because the government could say we would like you to store the state and we'll be back in a short amount of time to pick it up so i do think that it would that if we didn't if this court were not to require a warrant and it would be too easy for the government to go to service providers and ask for a record this information about her about people and of that it would be very then easy for the gov to or the provider to do that recording i also would like to respond to the notion that the key fact is what's in an ordinary business record or routine business record because that really is not the constitutional question but the question is whether or not the customer has assumed the risk of the disclosure of information by voluntarily providing it actively and knowingly to for use by the by the company and for view by the employees and that's what happened in miller and in the smith case and that's not at all what happens here because in these cases the information is generated automatically by the company without the knowledge or input or control of the user so i think that's a very important distinction between smith versus maryland and miller versus united states that that is a key distinction for our purposes in addition the the government makes much of the fact that this is non content information and i would just like to point out the for constitutional purposes that's not a significant categorization the court has never held that non content information is not protected by the fourth  merely held that the telephone numbers dialed were not protected not that any information that was not content is not protected and there are other supreme court cases which i found that information that is not content is nonetheless protect site location data is much richer and more revealing than the information in either smith or miller it can reveal in intimate information about our personal meetings with our friends our families and our socio the government wants the benefits of ask you one question right enough just to summarize for me in a few words if you can why you believe that the fourth amendment because users have a reasonable expectation of privacy in that data and because we should because we shouldn't live in a society where the law enforcement agents should be able to access the theater without subjecting themselves to judicial review provided by the but yes because it is a particularly intrusive technique that is powerful and subject to abuse that reveals personal data including data about things that go on in the home but that also can create a virtual  go like what we're going to reveal that goes on in the home well again i as michael am a key argue that it doesn't have to reveal specific information like when you're in the bath or what to reveal what they were nails for example when you're home how long you home it could easily reveal who is in your home with you if you have information more than one cell phone bills when you're awake if you're making calls how long you're away you know are you sending text messages perhaps are you sending your browsing your e mail midnight eight o'clock every day and then very quickly be able to tell that you were in your home so and as sort of the source like a piece of the puzzle it's a very revealing technique that is that is extremely intrusive into people's private lives devices right specifically excludes any communication from a tracking device from the definition of an electronic communication correct rob and so as you understand  doesn't permit the government to secure information from tracking devices without a warrant telling a probable cause i in which a tracking device i know go in which in which case a tracking device was installed and used and the ninth circuit held that no warrant was required the seventh circuit has followed suit in the garcia case in recent years  there is no substantial disagreement among the circuits so no the government is not required to use a warrant when it uses a tracking device there are occasions and the supreme court's decision in  there are occasions when the government by monitoring information from a tracking device may intrude upon a fourth amendment protected interest and the rule in care only set this forth both in our opening brief in a reply the rule is very that it is only when the government learns by monitoring the tracking device and solely by means of monitoring the tracking device about the presence of the tracked object within a specific protected space it's not enough to get to a multi unit storage facility was a warehouse where individuals could rent lockers but there were multiple offers the government tracked the object to that building it even tracked it to a specific row of lockers but not to a particular locker and the supreme court held explicitly that none of that activity constituted a fourth amendment search it would only have been have the government by means of monitoring the tracking device and how the records at issue in this case intrude upon the fourth amendment interests they cannot they do not have sufficient precision to reveal the presence of a telephone within any particular space even down to the most precise those records can be in a dense urban environment a few hundred meters and i think kero is controlling on that point what's the relevance of the fact that the definition of electronic communications exclude wire communications just to make clear that a particular communication your honor can only be one or the other it cannot be both at the same it would occasion to see change in law enforcement practice the government can compel preditions to telephone calling records by means of a grand jury subpoena but under the rule that's verged by any key here even though simple landline telephone calling record know i think the answer that is is fairly complicated one i'm not sure i'm competent to answer that question in the short time available to buy this but you accept the fact that historically that has been the standard