In the National Football League

National Football League

The National Football League is the highest level of professional American football in the United States, and is considered the top professional American football league in the world. It was formed by eleven teams in 1920 as the American Professional Football Association, with the league changing...

, an illegal procedure can be used to refer to one or any number of a set of penalties

Penalty (American football)

In American football and Canadian football, a penalty is a sanction called against a team for a violation of the rules, called a foul. Officials initially signal penalties by tossing a bright yellow or orange colored "penalty flag" onto the field toward or at the spot of a foul...

. It is not itself a particular penalty, but an encompassing term which can describe several infractions.

Types of illegal procedure

In many cases, most notably in the National Football League

National Football League

The National Football League is the highest level of professional American football in the United States, and is considered the top professional American football league in the world. It was formed by eleven teams in 1920 as the American Professional Football Association, with the league changing...

, this type of penalty has even been given its own signals. Examples of this include:

• Illegal shift
• Illegal motion
• Illegal forward pass
• Illegal touching of a forward pass
• Ineligible receiver downfield
  Ineligible receiver downfield
  In gridiron football, ineligible receiver downfield is a penalty that is called when a forward pass is thrown to a member of the offensive team who is not considered an eligible receiver by the rules of the game. In most leagues, the eligible receivers are the running backs, wide receivers, and...
  
  
• Illegal substitution

However, certain penalties still retain the "illegal procedure" signal. Examples of this are:

• False start
  False start
  In sports, a false start is a movement by a participant before being signaled or otherwise permitted by the rules to start...
  
  
• Illegal formation
• Kickoff or safety kick out of bounds
• Player voluntarily going out of bounds and returning to the field of play on a punt

Usage by the referee

Most penalties that are considered to fall under the category of "illegal procedure" are not stated as such when announced by the referee, as it may be considered insufficient explanation, and require further justification anyway. However, referees do often preface the less common penalties of "kickoff or safety kick out of bounds," and "player voluntarily going out of bounds" with, "illegal procedure," likely to avoid possible confusion caused by the signal with multiple meanings.

Usage at different levels

It is used similarly to the professional level at the high school level, but this term is not referenced at all in the collegiate rule book.