30 days
To complete your investigation after hire
30 days
For prior employers to respond to you
3 years
Look-back period for prior DOT employers
§391.53
Secure file where the records live
What §391.23 Actually Requires at Hire
When a motor carrier hires a CDL driver, 49 CFR 391.23(a) imposes two distinct investigation duties. First, the carrier must make an inquiry to each state where the driver held a motor vehicle operator's license in the preceding three years to obtain the driver's motor vehicle record (MVR). Second — and this is the part carriers most often under-document — the carrier must investigate the driver's safety performance history with every Department of Transportation regulated employer the driver worked for during the preceding three years.
These are not the same task, and one does not satisfy the other. The MVR comes from the state licensing authority. The safety performance history comes from the driver's previous DOT-regulated employers. A driver qualification file that contains a clean MVR but no documented previous-employer investigation is incomplete, and an FMCSA auditor will treat the missing investigation as a violation regardless of how good the MVR looks.
The 30-day window is the trap
Section 391.23(b) gives you 30 days from the driver's employment start date to complete the safety performance history investigation. Carriers routinely let drivers run loads for weeks while waiting on old employers, then discover at audit that the file shows no investigation and no documented good-faith effort. The regulation does not require the previous employer to have answered within your 30 days — it requires that within 30 days, your file contains either the responses or proof you tried.
The Two 30-Day Clocks: Yours and Theirs
The most confusing part of §391.23 is that it contains two separate 30-day periods that run in different directions. Understanding which clock is which keeps you out of trouble.
Your clock — §391.23(b)
Within 30 days of the driver's employment start date, you must place the previous employers' responses — or documentation of your good-faith efforts to contact them — into the driver investigation history file. This is the deadline FMCSA enforces against the carrier.
Their clock — §391.23(d)
A previous DOT-regulated employer must respond to your request within 30 days after the request is received. If they have nothing to report, they must still confirm that in writing with the driver's identification and dates of employment. This deadline binds the previous employer, not you.
Because the previous employer's 30 days can outlast your 30 days, the practical compliance move is to send your requests on day one, follow up, and document each attempt. Your file is judged on whether you made and recorded the requests within 30 days — not on whether every old employer cooperated.
What You Must Request
Section 391.23(d) and (e) specify the information you are required to seek from previous DOT-regulated employers. The request has two layers: general data that any previous employer must provide, and safety-sensitive testing data that DOT-regulated employers must provide.
| Information Requested | Regulation | Notes |
|---|---|---|
| General driver identification and employment verification | §391.23(d)(1) | Confirms the driver worked there and the dates of employment |
| Accident data from the prior 3 years | §391.23(d)(2) | As defined in §390.15(b)(1) — the accident register information |
| Alcohol tests with a result of 0.04 or higher | §391.23(e) | From DOT-regulated employers only |
| Verified positive controlled-substances test results | §391.23(e) | From DOT-regulated employers only |
| Refusals to be tested | §391.23(e) | Treated as a violation under Part 382 |
| Failure to complete a return-to-duty / SAP process | §391.23(e) | Other than tests administered as part of follow-up |
| FMCSA Clearinghouse drug & alcohol records | Clearinghouse (eff. Jan 6, 2023) | Much of the testing history now flows through the Clearinghouse query |
The Clearinghouse changed where the testing history comes from
Since January 6, 2023, the drug and alcohol program violation history that used to be obtained directly from previous employers under §391.23(e) is largely accessed through the FMCSA Drug and Alcohol Clearinghouse. Running a Clearinghouse query is a separate obligation under Part 382, but it now carries much of the safety performance history weight. You still send the §391.23 request for general and accident data; the testing-violation piece is increasingly a Clearinghouse function.
Documenting a Good-Faith Effort When Employers Go Silent
Old employers move, merge, and go out of business. The regulation anticipates this. Under 49 CFR 391.23(i), if you do not receive a response, you are not in violation as long as your record shows a documented good-faith effort. The record must include the previous employer's name and address, the date or dates you attempted contact, and any information you did receive.
A defensible good-faith effort looks like a sequence, not a single attempt. Send the request in writing at the start of employment, follow up at least once if no response arrives, and write down each contact with a date. A note in the file reading "called Acme Trucking 6/2, left message; emailed records request 6/2; mailed form 6/5; no response as of 6/30" is exactly the kind of contemporaneous record an auditor wants to see. It converts a non-response into documented compliance.
A compliant investigation record
- Request sent to every DOT-regulated employer from the prior 3 years
- Each contact dated and logged (call, email, letter)
- Responses — or documented non-responses — in the file within 30 days of hire
- Clearinghouse query run and saved
- Records kept in a secure, controlled-access location
- Used only for the hiring decision
What gets cited at audit
- No documented previous-employer investigation at all
- MVR on file but no safety performance history request
- Single attempt with no follow-up and no dated log
- Investigation completed long after the 30-day window
- Records stored where anyone can access them
- Driver dispatched with an empty investigation file
Where the Records Live: The §391.53 Driver Investigation History File
The safety performance history you collect does not go into the general personnel file or the public-facing DQF. Under 49 CFR 391.53, the responses and your investigation records are kept in a driver investigation history file maintained in a secure location with controlled access. Access is limited to people involved in the hiring decision or in administering the data. The information may be used only for the hiring decision.
Your insurer may access the file — with one carve-out: the alcohol and controlled-substances information is not available to the insurer. And the retention rule mirrors the rest of the DQF: the records are kept for as long as the driver is employed by the carrier and for three years thereafter. A carrier that collects the history but stores it loosely, or that purges it the day a driver quits, has its own compliance problem independent of whether the original investigation was done correctly.
Three rules for the investigation history file (§391.53)
- • Secure + controlled access — only hiring decision-makers can reach it.
- • Hiring use only — the data cannot be used for any other purpose.
- • Duration + 3 years — retain while employed and three years after.
How FileFlo Keeps the §391.23 Investigation Audit-Ready
FileFlo is the records and proof layer for driver qualification — not a background-check vendor or an MVR service. It does not run the previous-employer interviews for you, and it is not the Clearinghouse. What it does is make sure the investigation you performed is documented, complete, and instantly producible when an auditor asks for it.
- 30-day window tracking: Flag every new driver's investigation deadline from the employment start date so the previous-employer requests and good-faith documentation land in the file before day 30 — not after the auditor finds the gap.
- Contact-attempt log: Record each request, follow-up, and response with a date, building the contemporaneous good-faith-effort trail that §391.23(i) requires when a prior employer never answers.
- Secure investigation history file: Keep the safety performance history records organized as a controlled-access set consistent with §391.53, separate from the general DQF, retained for the duration of employment plus three years.
- Audit-ready export: When FMCSA opens a New Entrant Safety Audit or Compliance Review, export the complete investigation record for any driver in minutes instead of reconstructing who you called and when.
Key Takeaways
- You have 30 days from the driver's first day to complete the safety performance history investigation and file the responses or good-faith documentation (§391.23(b)).
- Previous employers have 30 days to respond after receiving your request, even if their only response is "no data" (§391.23(d)).
- The MVR inquiry and the previous-employer investigation are separate duties — one cannot substitute for the other (§391.23(a)).
- Document a good-faith effort with names, addresses, and dated contact attempts when an employer is silent or defunct (§391.23(i)).
- Store the records in a secure §391.53 file, use them only for hiring, and retain for the duration of employment plus three years.
Safety Performance History Inquiry: FAQ
Common questions about the 49 CFR 391.23 previous-employer investigation and the 30-day windows.
Under 49 CFR 391.23(b), a motor carrier must complete the investigation of a new driver's safety performance history with DOT-regulated employers from the preceding three years within 30 days of the date the driver's employment begins. The 30-day clock runs from the employment start date, not the application date or the hire decision. Within that window you must place either the previous employers' responses or documentation of good-faith efforts to contact them into the driver investigation history file required by 391.53.
Yes. Under 49 CFR 391.23(d), a previous DOT-regulated employer must respond to a safety performance history request within 30 days after the request is received. Even if the employer has no information to report for that driver, it must still send a response confirming there is no data, along with the driver identification and dates of employment. Your obligation is to make the request and document it; the previous employer's obligation is to answer within 30 days.
Under 49 CFR 391.23(d) and (e), you must request general driver identification and employment verification, plus accident data from the three years before the application as defined in 390.15(b)(1). You must also request, from DOT-regulated employers, alcohol and controlled-substances information: alcohol tests of 0.04 or higher, verified positive drug tests, refusals to test, and any failure to complete a return-to-duty process. As of January 6, 2023, much of the drug and alcohol violation history is queried through the FMCSA Clearinghouse rather than directly from prior employers.
You are not penalized for a previous employer's failure to respond, but you must document your good-faith effort. Under 49 CFR 391.23(i), if you do not receive a response, your record must show the previous employer's name and address, the dates you attempted contact, and any information received. A reasonable practice is to send the request, follow up at least once, and record each attempt with a date. The documented good-faith effort, placed in the driver investigation history file, satisfies the requirement when the prior employer is unreachable or defunct.
Under 49 CFR 391.53, safety performance history records obtained through the 391.23 investigation must be kept in a secure location with controlled access, separate enough that only people involved in the hiring decision can reach them. The data may be used only for the hiring decision. Your insurer may access the file, except for the alcohol and controlled-substances information. The records are retained for as long as the driver is employed plus three years thereafter.
No. Section 391.23(a) actually requires two separate things at hire: an inquiry to each state where the driver held a license in the past three years to obtain the motor vehicle record (the MVR), and the safety performance history investigation of prior DOT-regulated employers. The Pre-Employment Screening Program (PSP) report is a separate, voluntary FMCSA tool that pulls roadside inspection and crash data; it is not the 391.23 previous-employer investigation. A complete file generally includes all three, but they come from different sources and serve different regulatory purposes.
Never miss a §391.23 investigation deadline again
FileFlo tracks every new driver's 30-day investigation window, logs each previous-employer contact with a date, and keeps the §391.53 investigation history file organized and audit-ready. It is the records and proof layer for your DQFs — automated expiration alerts, gap detection, and one-click audit export.
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