---
title: Previous-employer safety performance history
description: How motor carriers investigate DOT-regulated employment under 49 CFR 391.23 and what belongs in the driver investigation history file.
date: 2026-10-20
lastReviewed: 2026-10-23
canonical: /resources/guides/previous-employer-safety-performance-history
---
Motor carriers must investigate each new driver’s **safety performance history** with DOT-regulated employers during the preceding three years, separate from the qualification file itself ([49 CFR 391.23(a)(2)](https://www.ecfr.gov/current/title-49/section-391.23), [391.53](https://www.ecfr.gov/current/title-49/section-391.53)).

## Short answer



Contact previous DOT-regulated employers (or use the Drug & Alcohol Clearinghouse for FMCSA-regulated history where the rule requires it), file each reply or your documented good-faith efforts within 30 days of the start date in a secure investigation history file, and keep alcohol and drug consent on file before the driver operates a CMV. Replies stay confidential to hiring decision-makers. DQid can store supporting documents; access and hiring decisions remain the carrier’s responsibility.



## What to investigate



### 
  

### 
    At minimum, ask prior employers about accidents involving the driver during
    the three years before the application, using the data elements in § 390.15.
  


  

### 
    From each previous DOT employer in a safety-sensitive function, investigate
    violations, failed rehabilitation, and post-referral testing issues listed
    in paragraph (e). FMCSA-regulated employers after January 6, 2023 use the
    Clearinghouse for much of this history.
  


  

### 
    Obtain consent that meets Part 40 rules before seeking alcohol and drug
    history. If the driver refuses consent for a Clearinghouse query, you must
    not permit the driver to operate a CMV.
  


  

### 
    Keep a written record of each previous employer contacted, the date, and
    what you received—or document failures to contact or to obtain data.
  


  

### 
    When no DOT-regulated employer existed in that period, document that no
    investigation was possible within the same 30-day window.
  





## Where the records live

Replies and consent forms belong in the **driver investigation history file**, not in the open qualification file ([49 CFR 391.53](https://www.ecfr.gov/current/title-49/section-391.53)). Limit access to people involved in the hiring decision.

## Driver review rights

Give the due-process notice before any hiring decision ([49 CFR 391.23(i)](https://www.ecfr.gov/current/title-49/section-391.23)). Drivers may request copies of investigative information, seek corrections from prior employers, or attach a rebuttal.


  Use investigation data only for hiring decisions, and protect it from wider
  disclosure as the rule requires.


## Sources

- [49 CFR 391.23 — Investigation and inquiries](https://www.ecfr.gov/current/title-49/section-391.23) (eCFR text reviewed 2026-10-20)
- [49 CFR 391.53 — Driver investigation history file](https://www.ecfr.gov/current/title-49/section-391.53) (eCFR text reviewed 2026-10-20)
- [49 CFR 382.701 — Drug and Alcohol Clearinghouse](https://www.ecfr.gov/current/title-49/section-382.701) (eCFR text reviewed 2026-10-20)