Found the info below in a 2017 article on sbnation.com I removed verbiage in the article that gave 2017 examples of the process.

NFL teams hiring a new head coach must follow these rules

There are rules that every team must follow when going through the process of hiring a new head coach
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The Rooney Rule

Teams can’t just interview one coach and hire that person right off the spot. Franchises have to follow the Rooney Rule.

The Rooney Rule, which was enacted in 2003, is a policy that mandates teams looking for a new head coach interview at least one minority candidate for head coaching and senior football operations positions.

Assistant coaches not in the playoffs

Teams can interview any assistant coaches from other teams who are not in the playoffs. They must, however, request permission if a coach is under contract with another team.

Teams can block a candidate from interviewing for a position that would be a lateral move, but can’t stop assistant coaches from interviewing for a position that is a promotion.

Assistant coaches with first-round bye in playoffs

Teams are also allowed to interview assistant coaches who have a first-round bye in the playoffs. However, the interview must take place that week. Candidates can choose to decline the interview to focus on preparing their current team for the postseason.

Assistant coach following a win or loss in the Wild Card round

If an assistant coach’s team loses in the Wild Card round, the candidate can interview with any team that goes through the proper channels to secure an interview. However, if the assistant coach’s team wins, teams need approval for an interview, which has to take place before the divisional round.

Interviews after the divisional round

No initial interviews can be requested or granted for candidates whose teams are still in the playoffs after the divisional round, i.e. anyone from the four teams vying for a conference championship.

Assistant coach with a team that advances to the Super Bowl

Teams are typically only allowed to interview a candidate one time while the candidate’s team is in the playoffs. However, there’s an exception to that rule for teams playing in the Super Bowl thanks to the two-week window between the conference championships and the big game itself.

If an assistant coach’s team advances to the Super Bowl, teams again need permission to schedule a second interview.

Once the assistant’s team has arrived to the Super Bowl site, the candidate can’t participate in an interview. The interview must take place the week after the Conference Championship, but before the team travels to the Super Bowl.

[www.sbnation.com]

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