The free pass, commonly referred to as the "lucky dog" or "beneficiary rule", is a rule in some motor racing leagues allowing the closest lapped driver to the front of the field to gain back a lap when a caution is called. The driver is called to move to the end of the longest line of the cars at the end of that caution period. This rule was instituted to prevent drivers from racing back to the start/finish line when a caution was called.

The rule was first implemented by NASCAR in the 2003 seasons of its three national series, and in all NASCAR-sanctioned series by 2005.

Before the rule was installed, drivers would "race back to the caution"; however, there was a gentlemen's agreement not to race, but to slow down and not pass, to allow slower cars to get their laps back. During the Sylvania 300 at New Hampshire International Speedway, Casey Mears came close to contacting the stalled car of Dale Jarrett while racing back to the line during a caution caused by Jarrett's crash. NASCAR chose to abandon the practice and stop racing immediately in the wake of the incident. The rule was created as a way of continuing the practice of yielding to the slower cars without sacrificing safety.

The popular term for this rule, "lucky dog", was first used by Benny Parsons in 2003 during a TNT broadcast at Dover International Speedway. His boothmate Wally Dallenbach Jr., concurred when Jimmy Spencer, who drove a car sponsored by Sirius Satellite Radio (whose company mascot was a dog, named "Deejay Mongobot"), saying, "That IS a lucky dog." This became used by all NBC and TNT broadcasts, along with the Performance Racing Network radio broadcasts. The term is also used by NASCAR SimRacing and iRacing, among other licensed NASCAR video games produced after the rule was implemented.

Another oft-used term, "free pass", was first used by Mike Joy during the 2004 broadcast of the Subway 400 at North Carolina Speedway in Rockingham, North Carolina. Sometimes, Larry McReynolds, especially during the 2004 season, would refer to it as a pardon (sometimes accompanied by "from the Oval Office"; "Oval Office" is a term referring to the NASCAR mobile office and the proper series logo), and sometimes Darrell Waltrip uses it only for the #38 Robert Yates Racing Ford and later #18 Joe Gibbs Racing Toyota, because that car is sponsored by Mars, Incorporated, which manufactures the Pedigree dog food brand. It is used by MRN Radio and Fox Sports by its main announcers, and is used by the Fox graphics package. (Between 2007 and 2014, TNT's coverage is produced by Fox Sports; as part of the 2009 restart rule changes, the TNT graphics package states the driver with the Free Pass and Wave-Around before the restart.)

On Speed Channel and ESPN the term "Aaron's Lucky Dog" (which is the Aaron's corporate mascot, and is part of its branding) is used. During ESPN broadcasts, it is used only when it is officially awarded. During ESPN broadcasts, Jerry Punch follows the code established by ESPN producer Neil Goldberg, using Free Pass (which was Goldberg's policy on Fox).

In the NASCAR Pinty's Series, the term "VTech Lucky Dog" is a contingency award among drivers who were granted free passes during the race. The highest-finishing driver who had earned a free pass lap wins a CAD 1,000 prize.

The use of the term "lucky dog" is often criticized by specific Fox staff members for not being informative and producer Neil Goldberg, who has since moved to ESPN.^{[citation needed]} Mike Joy has mocked the term on Fox broadcasts, first in March 2005 during the Busch Series Telcel-Motorola 200 at the Autodromo Hermanos Rodriguez, where a dog ran across the track during a caution, and in April 2006 during the DirecTV 500 in Martinsville Speedway, where Joy referred to Ryan Newman's love of pets and said despite his love of dogs, he hadn't been a lucky dog.^{[citation needed]}