The Department of Defense is clear:
DOD policy for service members is contained in Department of Defense Directive 1344.10, Political Activities for Members of the Armed Forces. It is DOD policy to encourage members of the armed forces to carry out the obligations of citizenship while keeping with the traditional concept that members on active duty should not engage in partisan political activity. All members of the armed forces, including active-duty members, members of the reserve components not on active duty, and retired members are prohibited from wearing military uniforms at political campaign or election events.
St Sen (and now GOP cand. for PA Gov) Doug Mastriano is retired from the US Military.
So why is this picture at his campaign website?
It's in a set of photos titled "Doug & Carrie Around Pennsylvania"
Yes, the website does contain this statement:
Doug Mastriano is a retired member of the United States Army. Use of his military rank, job titles, and photographs in uniform does not imply endorsement by the Department of the Army or the Department of Defense.But that's completely beside the point.
The image of Doug in uniform is posted on his campaign website. The set of photographs is of campaign events - or why else would it be on his campaign website? So there was at least one campaign event where Doug Mastriano wore his Class A uniform.
Even though (to reiterate) the DOD said this:
All members of the armed forces, including active-duty members, members of the reserve components not on active duty, and retired members are prohibited from wearing military uniforms at political campaign or election events.Any comment, Senator?