Your Friend Qualifies. Here is the law. All he needs is ID and qualification with the type of firearm he is going to carry.
Title 18 > Part 1 > Chapter 44 > § 926B
§ 926B. Carrying of Concealed Firearms by Qualified Law Enforcement Officers
(a) Notwithstanding any other provision of the law of any State or any political subdivision thereof, an individual who is a qualified law enforcement officer and who is carrying the identification required by subsection (d) may carry a concealed firearm that has been shipped or transported in interstate or foreign commerce, subject to subsection (b).
(b) This section shall not be construed to supersede or limit the laws of any State that—
(1) permit private persons or entities to prohibit or restrict the possession of concealed firearms on their property; or
(2) prohibit or restrict the possession of firearms on any State or local government property, installation, building, base, or park.
(c) As used in this section, the term “qualified law enforcement officer” means an employee of a governmental
agency who—
(1) is authorized by law to engage in or supervise the prevention, detection, investigation, or prosecution of, or the incarceration of any person for, any violation of law, and has statutory powers of arrest;
(2) is authorized by the agency to carry a firearm;
(3) is not the subject of any disciplinary action by the agency which could result in suspension or loss of police powers;
(4) meets standards, if any, established by the agency which require the employee to regularly qualify in the use of a firearm;
(5) is not under the influence of alcohol or another intoxicating or hallucinatory drug or substance; and
(6) is not prohibited by Federal law from receiving a firearm.
(d) The identification required by this subsection is the photographic identification issued by the governmental agency for which the individual is employed as a law enforcement officer.
(e) As used in this section, the term `firearm'--
(1) except as provided in this subsection, has the same meaning as in section 921 of this title;
(2) includes ammunition not expressly prohibited by Federal law or subject to the provisions of the National Firearms Act; and
(3) does not include--
(A) any machinegun (as defined in section 5845 of the National Firearms Act);
(B) any firearm silencer (as defined in section 921 of this title); and
(C) any destructive device (as defined in section 921 of this title).
(f) For the purposes of this section, a law enforcement officer of the Amtrak Police Department, a law enforcement officer of the Federal Reserve, or a law enforcement or police officer of the executive branch of the Federal Government qualifies as an employee of a governmental agency who is authorized by law to engage in or supervise the prevention, detection, investigation, or prosecution of, or the incarceration of any person for, any violation of law, and has statutory powers of arrest.
Title 18 > Part 1 > Chapter 44 > § 926C
§ 926C. Carrying of Concealed Firearms by Qualified Retired Law Enforcement Officers
(a) Notwithstanding any other provision of the law of any State or any political subdivision thereof, an individual who is a qualified separated from service law enforcement officer and who is carrying the identification required by subsection (d) may carry a concealed firearm that has been shipped or transported in interstate or foreign commerce, subject to subsection (b).
(b) This section shall not be construed to supersede or limit the laws of any State that—
(1) permit private persons or entities to prohibit or restrict the possession of concealed firearms on their property; or
(2) prohibit or restrict the possession of firearms on any State or local government property, installation, building, base, or park.
(c) As used in this section, the term “qualified retired law enforcement officer” means an individual who—
(1) separated from service in good standing from service with a public agency as a law enforcement officer, (2) before such separation, was authorized by law to engage in or supervise the prevention, detection, investigation, or prosecution of, or the incarceration of any person for, any violation of law, and had statutory powers of arrest;
(3)
(A) before such separation, served as a law enforcement officer for an aggregate of 10 years or more; or
(B) separated from service with such agency, after completing any applicable probationary period of such service, due to a service-connected disability, as determined by such agency;
(4) during the most recent 12-month period, has met, at the expense of the individual, the standards for qualification in firearms training for active law enforcement officers, as determined by the former agency of the individual, the State in which the individual resides or, if the State has not established such standards, either a law enforcement agency within the State in which the individual resides or the standards used by a certified firearms instructor that is qualified to conduct a firearms qualification test for active duty officers within that State; and
(5)
(A) has not been officially found by a qualified medical professional employed by the agency to be unqualified for reasons relating to mental health and as a result of this finding will not be issued the photographic identification as described in subsection (d)(1); or
(B) has not entered into an agreement with the agency from which the individual is separating from service in which that individual acknowledges he or she is not qualified under this section for reasons relating to mental health and for those reasons will not receive or accept the photographic identification as described in subsection (d)(1);
(6) is not under the influence of alcohol or another intoxicating or hallucinatory drug or substance; and
(7) is not prohibited by Federal law from receiving a firearm.
(d) The identification required by this subsection is—
(1) a photographic identification issued by the agency from which the individual separated from service as a law enforcement officer that indicates that the individual has, not less recently than one year before the date the individual is carrying the concealed firearm, been tested or otherwise found by the agency to meet the active duty standards for qualification in firearms training as established by the agency to carry a firearm of the same type as the concealed firearm; or
(2)
(A) a photographic identification issued by the agency from which the individual separated from service as a law enforcement officer; and
(B) a certification issued by the State in which the individual resides or by a certified firearms instructor that is qualified to conduct a firearms qualification test for active duty officers within that State that indicates that the individual has, not less than 1 year before the date the individual is carrying the concealed firearm, been tested or otherwise found by the State or a certified firearms instructor that is qualified to conduct a firearms qualification test for active duty officers within that State to have met--
(I) the active duty standards for qualification in firearms training, as established by the State, to carry a firearm of the same type as the concealed firearm; or
(II) if the State has not established such standards, standards set by any law enforcement agency within that State to carry a firearm of the same type as the concealed firearm; and
(e) As used in this section--
(1) the term `firearm'--
(A) except as provided in this paragraph, has the same meaning as in section 921 of this title;
(B) includes ammunition not expressly prohibited by Federal law or subject to the provisions of the National Firearms Act; and
(C) does not include--
(i) any machinegun (as defined in section 5845 of the National Firearms Act);
(ii) any firearm silencer (as defined in section 921 of this title); and
(iii) any destructive device (as defined in section 921 of this title); and
(2) the term `service with a public agency as a law enforcement officer' includes service as a law enforcement officer of the Amtrak Police Department, service as a law enforcement officer of the Federal Reserve, or service as a law enforcement or police officer of the executive branch of the Federal Government.
Title 18 > Part 1 > Chapter 44 > § 927
§ 927. Effect on State law
No provision of this chapter shall be construed as indicating an intent on the part of the Congress to occupy the field in which such provision operates to the exclusion of the law of any State on the same subject matter, unless there is a direct and positive conflict between such provision and the law of the State so that the two cannot be reconciled or consistently stand together.