Colin Dalawn Jackson (“Jackson”) appeals his conviction and sentence, following a jury trial, for conspiring to possess with intent to distribute more than five kilograms of cocaine, in violation of 21 U.S.C. § 846. Jackson primarily argues that the district court erred in admitting into evidence two notebooks received from Jackson’s alleged coconspirator during a proffer session. The coconspirator did not testify or otherwise authenticate the notebooks, but they purportedly show the quantity of cocaine the coconspirator distributed to Jackson. Jackson contends that admitting the notebooks, and an investigating officer’s testimony pertaining thereto, violated the Confrontation Clause of the Sixth Amendment; that the notebooks and testimony constitute hearsay; and that the notebooks lacked sufficient authentication. Because the notebooks were not sufficiently authenticated, we hold that the district court abused its discretion in admitting the notebooks into evidence at trial, that this error violated Jackson’s rights under the Confrontation Clause, and that the error was not harmless. We further hold that the evidence was sufficient to sustain Jackson’s conviction absent admission of the notebooks into evidence. We therefore vacate the district court’s judgment of conviction and sentencing and remand for further proceedings not inconsistent with this opinion.
I.
A federal grand jury indicted Jackson on April 22, 2008, on a single count of conspiring with Arturo Valdez (‘Valdez”) and other known and unknown persons, beginning on or about December 1, 2006 and continuing through August 1, 2007, to possess with intent to distribute more than five kilograms of cocaine. The evidence at trial included the following: Officer Christopher Hight, a Dallas police officer and task force officer of the Drug Enforcement Administration (DEA), testified that he was involved in surveillance and interception of communications concerning various drug cartels, including a drug-trafficking organization headed by one Juan Reyes-Mejia. Hight testified that he and other officers had identified a cell operating within this organization, headed by Arturo Valdez. Valdez worked as a cocaine distributor in the larger drug-trafficking organization, collected money from the sale of cocaine that he transferred to couriers for transport to Mexico, had customers of his own, and was a trusted member of the drug-trafficking cartel.
Wiretap surveillance disclosed multiple conversations that Valdez had with an individual identified in the phone conversations as “Cory.” Hight testified that he became familiar with Cory’s voice over the course of the surveillance and, having subsequently spoken with the defendant, Hight testified that “Cory’s” voice was that of the defendant, Mr. Jackson. The jury heard several recordings of the phone conversations between Valdez and “Cory,” and Valdez and other persons, which Hight interpreted for the jurors as reflecting plans to engage in various cocaine and other narcotics transactions.
In August 2007, a task force arrested over 30 individuals involved in wide-rang*879ing alleged drug-trafficking conspiracies. Valdez was arrested by DEA agents on August 16, 2007. Apparently seeking to work out a plea agreement and obtain leniency at sentencing, Valdez agreed to a proffer session with law enforcement concerning his knowledge of the drug-trafficking conspiracy. During that session, Valdez and his attorney produced, without comment as far as the record is concerned, two notebooks to Officer Hight containing 78 pages of handwriting, with numbers, notations, and names. Certain lines of text in the notebooks appear to be names or abbreviations for names. The names “Cory,” “Corey” and “Cor.” appear in several places in the notebooks; the government’s witness testified that these writings identify Jackson. Alongside and beneath several of the alleged references to Jackson are various numbers. The government’s witness testified, and the government asserted in its closing argument, that these numbers reflect payments and amounts of cocaine, totaling approximately 350 kilograms, that were given to Jackson in the course of a conspiracy to possess and distribute cocaine.
The government introduced the notebooks at trial solely through the testimony of Officer Hight, who twice stated that his analysis of them was “based on [his] experience as an officer and nothing from what was obtained from Mr. Valdez.” Officer Hight further testified why drug traffickers often keep ledgers, and he explained the various entries in the ledgers that he interpreted as representing cocaine transactions involving Jackson. He testified that he believed the numbers in the notebooks reflect quantities of cocaine, rather than marijuana, because the numbers are consistent with information the police had gathered through telephone surveillance. Hight also stated that the ledgers’ references to “Nove” and “Nov.” are references to Noe Godines, another participant in the drug conspiracy. Hight testified at length concerning the notebooks’ contents, interpreting various numbers and calculations for the jury.
At trial, Jackson objected to admission of the notebooks on Sixth Amendment, hearsay, and authentication grounds. These objections were overruled, and the jury found Jackson guilty of one count of conspiring to possess with intent to distribute more than five kilograms of cocaine.1 Jackson timely appealed to this Court.
II.
The threshold question before us is whether the notebooks purporting to be drug ledgers were properly authenticated such that they fall within a recognized exception to the Confrontation Clause. The government argues that the notebooks are nontestimonial business records that by their nature do not offend the Confrontation Clause. Alternatively, the government contends that the notebooks are nontestimonial statements made by a co-conspirator during the course and in furtherance of a conspiracy.
In this case, proper authentication of the notebooks is determinative of whether the introduction of that evidence violated the Constitution, ie., the Confrontation Clause.2 Review of a trial court’s evidentiary rulings is for abuse of discretion, subject to harmless error review.3 United States v. Jimenez Lopez, 873 F.2d *880769, 771 (5th Cir.1989). “A trial court abuses its discretion when its ruling is based on an erroneous view of the law or a clearly erroneous assessment of the evidence.” United States v. Yanez Sosa, 513 F.3d 194, 200 (5th Cir.2008) (internal citations omitted).
Applying the foregoing standard, we conclude that the district court abused its discretion in admitting the notebooks given to Officer Hight by Arturo Valdez because they were not properly authenticated. The notebooks fall outside of the business records and coconspirator statement exceptions to Crawford and, as presented to the jury here, are testimonial in nature.
A.
A properly introduced, authenticated business record that meets the standards of the Federal Rules of Evidence ordinarily is nontestimonial and will not violate the Confrontation Clause. Thus, we first address whether the notebooks were properly authenticated as business records in accordance with Federal Rule of Evidence 803(6).4 In Crawford v. Washington, the Supreme Court held that “[wjhere testimonial evidence is at issue, ... the Sixth Amendment demands what the common law required: unavailability and a prior opportunity for cross-examination.” 541 U.S. 36, 68, 124 S.Ct. 1354, 158 L.Ed.2d 177 (2004). While the Court did not define “testimonial,” it noted that business records fall outside this category. Id. at 56, 124 S.Ct. 1354. In general, “after Crawford, business records are not testimonial in nature and their admission at trial is not a violation of the Confrontation Clause.”5 United States v. Morgan, 505 F.3d 332, 339 (5th Cir.2007).
The Confrontation Clause claim before us today turns on authentication of the *881notebooks. If the notebooks were not properly authenticated, then they do not qualify as business records and their admission into evidence violates the Confrontation Clause. We reach this conclusion here because the notebooks contain entries that, when offered into evidence as records of regular business activity, purport to be Arturo Valdez’s “solemn declaration[s] or affirmation[s] made for the purpose of establishing or proving some fact[s]” — namely, the existence and amounts of his cocaine transactions with Jackson. Crawford, 541 U.S. at 51, 124 5.Ct. 1354. If not authentic business records, the ledger entries are merely statements, made at an unknown time and conveyed at a proffer session, that relate (through Officer Hight’s translation for the jury) the very testimony that Valdez “would be expected to provide if called at trial.” Melendez-Diaz, 129 S.Ct. at 2532. Irrespective of the fact that they were volunteered, the notebook entries “do precisely what a witness does on direct examination.” Davis v. Washington, 547 U.S. 813, 830, 126 S.Ct. 2266, 165 L.Ed.2d 224 (2006); see also id. at 822 n. 1, 126 S.Ct. 2266 (“The Framers were no more willing to exempt from cross-examination volunteered testimony ... than they were to exempt answers to detailed interrogation”).
The government plainly introduced the notebooks to prove the truth of the matter asserted: Jackson’s transacted cocaine deals with Valdez. Valdez did not appear at trial, was not shown to be unavailable for trial, and was not cross-examined. Thus it is clear that in this case, if the ledgers do not satisfy the requirements of business records, they are prohibited as testimonial evidence that violates the Confrontation Clause. See United States v. Gonzales, 436 F.3d 560, 576 (5th Cir.2006) (“[T]he Confrontation Clause prohibits (1) testimonial out-of-court statements; (2) made by a person who does not appear at trial; (3) received against the accused; (4) to establish the truth of the matter asserted; (5) unless the declarant is unavailable and the defendant had a prior opportunity to cross examine him.”).
“The requirement of authentication or identification as a condition precedent to admissibility is satisfied by evidence sufficient to support a finding that the matter in question is what its proponent claims.” Fed.R.Evid. 901(a). “A proponent may authenticate a document with circumstantial evidence, including the document’s own distinctive characteristics and the circumstances surrounding its discovery.”6 In re McLain, 516 F.3d 301, 308 (5th Cir.2008) (internal citations omitted). “[T]his Court does not require conclusive proof of authenticity before allowing the admission of disputed evidence .... Rule 901 does not limit the type of evidence allowed to authenticate a document. It merely requires some evidence which is sufficient to support a finding that the evidence in question is what its proponent claims it to be.” Jimenez Lopez, 873 F.2d at 772. The standard for authentication is not a burdensome one. United States v. Barlow, 568 F.3d 215, 220 (5th Cir.2009). However, the government has failed to meet it in this case.
1.
The government argues that the notebooks were properly admitted as non-*882testimonial business records generated in the regular course of Mr. Valdez’s drug-trafficking enterprise. The first question presented is whether Officer Hight is a “qualified witness” for authentication purposes. Under Rule 803(6), “either the custodian of the business records or ‘other qualified witness’ [must] lay a foundation before the records are admitted.” United States v. Brown, 553 F.3d 768, 792 (5th Cir.2008). The witness must make some showing (1) that the notebooks record “acts, events, conditions, opinions, or diagnoses;” (2) that the record was made “at or near the time” those events or conditions took place; (3) that the record was made “by, or from information transmitted by, a person with knowledge;” (4) that the record was made “in the course of a regularly conducted business activity;” and (5) that “it was the regular practice of that business activity” to make such a record. Fed. R.Evid. 803(6). “ ‘There is no requirement that the witness who lays the foundation be the author of the record or be able to personally attest to its accuracy.’ ” Brown, 553 F.3d at 792 (quoting United States v. Duncan, 919 F.2d 981, 986 (5th Cir.1990)). Rather, “ ‘[a] qualified witness is one who can explain the record keeping system of the organization and vouch that the requirements of Rule 803(6) are met.’ ” Id. (quoting United States v. Iredia, 866 F.2d 114, 120 (5th Cir.1989)).
We have applied these principles in Brown, where we held that the district court properly excluded testimony from an expert witness called to lay the foundation for business records from a pharmacy’s computer system. Although he had never worked at the pharmacy in question, the witness “knew the [pharmacy’s computer] program well and had statistics training that allowed him to parse and present the large amounts of data in the records clearly.” Id. We found this insufficient for purposes of Rule 803(6). Specifically, we stated that the witness’s “expertise in statistics and in the computer program used did not give him any knowledge about [the pharmacy’s] record keeping practices. He knew about the pharmacy computer system, how to operate the system, and how to extract information from it, but that is not knowledge about the pharmacy’s record keeping.” Id. at 793.
Brown informs this case in clear terms. It is not the record keeping of drug-trafficking organizations generally that is most relevant; the records must be authenticated by someone with at least some knowledge of the record keeping of the particular distribution cell operated by Arturo Valdez. Officer Hight was the only witness called by the government to lay a foundation of authenticity for the notebooks.7 He testified that Valdez handed over these ledgers to him in the course of a discussion of a proffer, that is, hoping to get a better deal for himself. Hight did not testify that Valdez had said anything when producing the ledgers which allegedly incriminate others. Thus the record before us does not reflect who actually prepared these ledgers and entries and under what circumstances. Neither Valdez nor any other member of the drug-trafficking organization testified that the ledgers were kept in the regular course of a drug-trafficking enterprise. Cf. Duncan, 919 F.2d at 986-87 (upholding the admission of insurance company records where representatives of the insurance companies testified that those records were kept in the regular course of the companies’ business). Hight did testify that his analysis of the notebooks was based on their contents and his experience as a drug enforcement officer. While he *883spoke as one familiar with drug ledgers generally, he certainly did not speak as a member of the drug-trafficking organization or as one with knowledge of Valdez’s ledger-keeping practices. We therefore hold that “[a]midst all of his unquestioned expertise,” Officer Hight did not have the “necessary familiarity” with the record-keeping procedures of Valdez’s drug-trafficking cell. Brown, 553 F.3d at 792.
Nor could Officer Hight vouch that other requirements of Rule 803(6) had been met. See id. Presented with facts analogous to those in the instant case, we recently held that a trial court abused its discretion in admitting spreadsheets into evidence as business records because the witness was not qualified to authenticate the documents. See CFTC v. Dizona, 594 F.3d 408, 416 (5th Cir.2010). The investigator admitted that she had not interviewed any employee of the company regarding its record keeping, that she did not know whether the spreadsheets were made at or near the time of the recorded commodities trade, and that she did not know whether the spreadsheets were made by a person with knowledge of the trade. Id. Similarly, there is no evidence that Officer Hight interviewed Valdez or anyone else about the drug-trafficking organization’s record keeping. Hight acknowledged that the events recorded in the ledgers could have taken place at a time outside of the course of the conspiracy. Moreover, as we have explained, the record does not reflect whether the ledgers were prepared by someone with knowledge of the recorded transactions. In the light of this testimony, we hold that Officer Hight was not a qualified witness for purposes of authentication because the government submitted no evidence that he had knowledge — either first or second hand — of the Valdez organization’s record-keeping practices, and because Hight could not vouch that the requirements of Rule 803(6) had been met.
2.
We specifically repeat ourselves to remind that authentication of a business record requires a showing (1) that it records acts, events, conditions, opinions, or diagnoses; (2) that the record was made at or near the time those events took place; (3) that the record was made by, or from information transmitted by, a person with knowledge; (4) that the record was made in the course of a regularly conducted business activity; and (5) that it was the regular practice of that business activity to make such a record. Fed.R.Evid. 803(6). Even if all of these requirements are met, however, Rule 803(6) is not satisfied if “the source of information or the method or circumstances of preparation indicate lack of trustworthiness.” Id. Thus, as we have previously held, under Rule 803(6) great emphasis is placed on the reliability or trustworthiness of the records being introduced. United States v. Veytia-Bravo, 603 F.2d 1187, 1189 (5th Cir.1979). The evidence before us casts substantial doubt upon the notion that the ledgers in this case can be trusted as records kept in the course of a regularly conducted business activity.
Although we have not spelled out the precise contours of trustworthiness necessary to authenticate drug ledgers, we have upheld the authenticity of drug ledgers as business records where (1) the ledgers were found in the home of a known drug trafficker, and the government’s witness testified (2) that he worked for the drug trafficker who allegedly created the ledgers; (3) that the ledgers resembled those which the drug trafficker maintained; and (4) that the handwriting on the ledgers was similar to the drug trafficker’s *884handwriting. United States v. Arce, 997 F.2d 1123, 1128 (5th Cir.1993).
This case, however, is distinguishable in critical ways. Although there is no dispute that Mr. Valdez is a known drug trafficker, the ledgers were not found in Valdez’s home; they were produced by Valdez at a proffer session, under circumstances that raise questions in and of themselves. Officer Hight conceded that one of Valdez’s motives in turning over the ledgers was to obtain a benefit for himself. We have no information in the record to indicate that Valdez told Officer Hight that he was the recorder of the ledgers. No handwriting analysis was performed on the notebooks, and no member of the drug-trafficking organization testified relating to their trustworthiness. For his part, Officer Hight testified that he was not able personally to vouch for the credibility of any entries in the ledgers. The reliability of the notebooks is not redeemed by any visible characteristics identified in the record. The ledger entries do not include the term “cocaine” and thus do not facially convey that they are applicable to the conspiracy charged. There are no dates recorded on the ledgers other than a lone reference in each to February 9 (without a year). These features simply reinforce our conclusion that Valdez’s notebooks do not bear sufficient indicia of reliability to qualify them as admissible records kept in the course of a regularly conducted business activity.8
3.
We certainly do not overlook that the trial judge exercises broad discretion in ruling on the admissibility of evidence. Veytia-Bravo, 603 F.2d at 1189. But here the district court gave no reasons for its decision to admit the notebooks; it simply admitted the ledgers without comment. As the foregoing discussion makes clear, there is very little support for qualifying these ledgers as admissible business records under Rule 803(6). Indeed, the government has failed to satisfy virtually all of the authentication requirements with respect to the alleged drug ledgers, and the district court has said nothing. Thus satisfied that the district court’s assessment of the evidence was clearly erroneous, we conclude that admission of the notebooks under the business records exception was an abuse of discretion.
B.
Like business records, statements made by a coconspirator during the course and in furtherance of a conspiracy fall within a recognized exception to the hearsay rules. Feb.R.Evid. 801(d)(2)(E). Such statements “are by their nature generally nontestimonial and thus are routinely admitted against an accused despite the ab*885sence of an opportunity for cross-examination.” United States v. Holmes, 406 F.3d 337, 348 (5th Cir.2005). As with business records, documents purporting to be the statements of a coconspirator made in the course and in furtherance of a conspiracy must be authenticated in order to be admissible.
Whether the notebooks represent coconspirator statements made during and in furtherance of a conspiracy depends on whether Valdez made those records in the course of his drug-trafficking enterprise. We have already found the evidence insufficient for authentication on these grounds. Given this lack of predicate, we hold there is not a sufficient basis to find that the notebooks are coconspirator statements in furtherance of a conspiracy.
III.
Having concluded that the admission of the notebooks was an abuse of discretion that violated Jackson’s Confrontation Clause rights, we turn now to whether this error was harmless. For the reasons that follow, we hold that the error was not harmless beyond a reasonable doubt.
“A defendant convicted on the basis of constitutionally inadmissible Confrontation Clause evidence is entitled to a new trial unless it was harmless in that ‘there was [no] reasonable possibility that the evidence complained of might have contributed to the conviction.’” United States v. Alvarado-Valdez, 521 F.3d 337, 341 (5th Cir.2008) (quoting Chapman v. California, 386 U.S. 18, 24, 87 S.Ct. 824, 17 L.Ed.2d 705 (1967)) (internal citations omitted). If “the government’s closing argument relied on [the] very evidence” that offends the Confrontation Clause, then “[w]e cannot see how the government can conclusively show that the tainted evidence did not contribute to the conviction.” Id. at 342-43.
In its closing argument in this case, the government clearly relied on the drug ledgers provided to Officer Hight by Arturo Valdez. The government’s attorney explicitly stated that the ledgers showed cocaine distribution in excess of 350 to 400 kilograms to Mr. Jackson, and that these entries amount to proof beyond a reasonable doubt of Jackson’s participation in the conspiracy with Valdez. In the light of this reliance, and notwithstanding the other evidence implicating Jackson in the conspiracy — which, we acknowledge, is very substantial and clearly sufficient to support the conviction even in the absence of the ledgers — the government cannot conclusively show, under controlling precedents, that the notebooks did not contribute to the conviction. The trial court’s error was not harmless beyond a reasonable doubt.9
IV.
Our holding thus requires us to vacate Jackson’s conviction and remand for further proceedings. We do so because the evidence in the record is sufficient for a reasonable jury to convict Jackson even when the drug ledgers are excluded. This other evidence includes a number of telephone conversations, referred to earlier in this opinion, between Jackson and his alleged coconspirator Valdez regarding the sale and purchase of cocaine, which are sufficient, in and of themselves, to support a finding of guilt beyond a reasonable doubt. See United *886States v. Watkins, 591 F.3d 780, 788 (5th Cir.2009) (“Each element” of a conspiracy to possess and distribute more than five kilograms of cocaine “may be inferred from circumstantial evidence; that is, the ‘agreement may be inferred from a concert of action’ and ‘[k]nowledge of a conspiracy and voluntary participation ... may be inferred from a collection of circumstances.’”) (quoting United States v. Casilla, 20 F.3d 600, 603 (5th Cir.1994) (internal citations omitted)). The connection between Jackson and Valdez is further substantiated by photographs of the two men together. Under a review for sufficiency, this evidence must be viewed in the light most favorable to the verdict, giving “full play to the responsibility of the trier of fact fairly to resolve conflicts in the testimony, to weigh the evidence, and to draw reasonable inferences from basic facts to ultimate facts.” Jackson v. Virginia, 443 U.S. 307, 319, 99 S.Ct. 2781, 61 L.Ed.2d 560 (1979). To be sure, on appeal Jackson does not argue the insufficiency of the evidence for conviction. We therefore conclude that the remaining evidence is clearly sufficient to support a reasonable jury’s finding that Jackson conspired to possess with intent to distribute more than five kilograms of cocaine. Accordingly, Jackson’s conviction is vacated and the case is remanded for further appropriate proceedings, including an opportunity for a new trial.
V.
We sum up: Under the general exception to the Confrontation Clause for business records, ledgers allegedly containing records of cocaine transactions involving the defendant must be authenticated in order to be admissible. For an authenticating witness to be “qualified” for purposes of Rule 803(6), he or she must be able to explain the record-keeping system of the organization that made the records in question and vouch that the requirements of Rule 803(6) are met. Under this standard, the government witness proffered to authenticate the ledgers in this case was not a “qualified witness.” The government witness did not have knowledge of the record-keeping procedures of the drug-trafficking cell led by the coconspirator, nor was he able to vouch that the requirements of Rule 803(6) had been met. Observing that the primary emphasis of Rule 803(6) is on reliability and trustworthiness of the evidence, we have further held that the ledgers in this case did not bear sufficient indicia of reliability for purposes of authentication. We have thus concluded that the district court abused its discretion in admitting the notebooks into evidence without explanation, and that this error violated Jackson’s rights under the Confrontation Clause. Because the government relied on this inadmissible evidence in its closing argument, there is at least a reasonable possibility that the evidence contributed to the jury’s verdict. Thus, the district court’s error was not harmless. Finally, we hold that the remaining evidence against Jackson was sufficient to support the conviction, and that therefore this case is remanded for an opportunity for a new trial and such other proceedings as are appropriate.
For the foregoing reasons, the judgment of the district court is VACATED and the case is REMANDED for further proceedings not inconsistent with this opinion.
VACATED and REMANDED.
. Jackson’s 235-month prison sentence was based largely on drug-quantity calculations made using information in the drug ledgers supplied by Valdez and admitted at trial.
. See discussion infra Part II.A.
.We note that we have said on more than one occasion that our review of evidentiary rulings is heightened in criminal cases. See, e.g., United States v. Garcia, 530 F.3d 348, 351 (5th Cir.2008); United States v. Yanez Sosa, *880513 F.3d 194, 200 (5th Cir.2008); United States v. Gutierrez-Farias, 294 F.3d 657, 662 (5th Cir.2002). Although this standard has never been fleshed out or defined, we need not bother to do so because we need not heighten our scrutiny of the trial court’s discretion to arrive at the conclusion we reach today.
. Rule 803(6) provides an exception to the hearsay rule for
[a] memorandum, report, record, or data compilation, in any form, of acts, events, conditions, opinions, or diagnoses, made at or near the time by, or from information transmitted by, a person with knowledge, if kept in the course of a regularly conducted business activity, and if it was the regular practice of that business activity to make the memorandum, report, record or data compilation, all as shown by the testimony of the custodian or other qualified witness, or by certification that complies with Rule 902(11), Rule 902(12), or a statute permitting certification, unless the source of information or the method or circumstances of preparation indicate lack of trustworthiness. The term “business” as used in this paragraph includes business, institution, association, profession, occupation, and calling of every kind, whether or not conducted for profit.
Fed.R.Evid. 803(6).
. We recognize, of course, that there may be exceptions to this general observation because the Confrontation Clause, as a constitutional right, cannot be circumscribed by merely invoking the evidentiary rules of hearsay. For example, although ”[d]ocuments kept in the regular course of business may ordinarily be admitted at trial despite their hearsay status, ... that is not the case if the regularly conducted business activity is the production of evidence for use at trial.” Melendez-Diaz v. Massachusetts, — U.S. - , 129 S.Ct. 2527, 2538, 174 L.Ed.2d 314 (2009). Indeed, ”[b]usiness and public records are generally admissible absent confrontation not because they qualify under an exception to the hearsay rules, but because — having been created for the administration of an entity's affairs and not for the purpose of establishing or proving some fact at trial — they are not testimonial.” Id. at 2539-40. That is, business records are not per se nontestimonial, but they are generally so.
. We have further held that Crawford does not apply to the foundational evidence offered to authenticate business records in preliminary determinations of the records’ admissibility. Morgan, 505 F.3d at 339. Thus we need not address Jackson's claim that the testimony Officer Hight offered to authenticate the notebooks violated his rights under the Confrontation Clause.
. The custodian of the notebooks, Arturo Valdez, did not testify.
. In some settings, outside the business records exception, we have held that a witness's direct knowledge of the particular interactions recorded in a document is sufficient to establish that witness’s qualification to authenticate the document. See Barlow, 568 F.3d at 220 (upholding the authenticity of online-chat transcriptions by one who participated in and thus had direct knowledge of the chats). But here the government has not shown that Officer Hight had direct knowledge of the transactions allegedly recorded in the notebooks. To be sure, Officer Hight had listened to a number of telephone calls between Valdez and Jackson. He testified that he believed numbers in the notebooks represent quantities of cocaine because they are consistent with information he gathered from intercepted phone calls, whatever this general and unspecific observation may actually mean. However, Officer Hight did not connect any specific numbers recorded in the ledgers with amounts of cocaine that he had heard discussed during telephone surveillance; nor did he participate in or observe any of the alleged transactions that Valdez's ledgers purport to record.
. In the light of this conclusion, we need not address Jackson's additional grounds for appeal.