What does the gray color of a US citizen's passport mean?

AT The United States, like many other countries, has several types of passports that are valid for entry into and stay in foreign countries. However, relatively recently, in 2016, the so-called “service passport” was introduced into circulation.

Types of passports in the United States of America

There are four types of civil passports issued in the United States today. They can be easily distinguished by the color of the covers. More than 44 million people have ordinary blue-covered passports.

About 400,000 people have official burgundy passports, most of them active military personnel and members of their families. About 80,000 Americans have diplomatic passports with a black cover.

But in February 2016, the US State Department, in its diplomatic note, notified other states of the introduction of a new type of passport. The new passport is marked as "Service Passport" and has a gray cover.

The new "Service Passport" is a full-fledged independent document proving the identity of a US citizen in the same way as the "blue" US passport. However, it notes:

"The holder of this passport is on a trip abroad with the support of the US Government" [source. DN 16-1940 dated 07.12.2016]

The State Department announcement also acknowledges the assistance that will be provided to holders of the new Service Passport to facilitate their important work in support of the United States.

Differences between US passports with "special" cover colors

So what is the essence of the introduction of a new type of passport and how it differs from the "black" diplomatic and "burgundy" official passports.

1. "Black" passport issued to diplomats and persons related to the implementation of diplomatic functions. First level of priority.
2. "Burgundy" passport issued to officials or employees of the US government, as well as to military personnel in case of traveling abroad on duty. Second level of priority.
3. "Grey" passport issued to certain individuals providing services to the United States. These persons do not apply to citizens traveling abroad on the basis of a contract with the US government. Third level of priority.

In a word, the gray color of the passport cover indicates that its owner is traveling to fulfill work in support of the US government, while indicating that he has a lower level relationship with the US government, which does not entitle him to a diplomatic or official passport.