Is it legal for my employer to keep me from receiving copies for my certificate form my employment f

About a week ago, I started seeking different employment opportunities; I have been working with my current employer for 6 years, and started looking for something else due to need of more money. I work as a security subcontractor for a large payroll company and made an application for employment with the company we subcontract. I also made applications with various companies as well. I work as a security officer and have educations in administrations so I was seeking something in office field I had spoke to me branch manager 2 years ago about searching for some advance in my education field, he said he would try to assist me in anyway with pursuing my field, however I called the branch office of my company to request for my certificates of achievement, the operations manger of my branch got very angry with me that I was seeking other employment and that I had applied for one of there clients (the subcontractor I work for now), He went on to say he will fine the subcontractor if they hire me, because there is a case in there contract they can’t hire internally and security contracted to work for them. Also he said I can’t have any copies of my certificates by law and there polices, I can only view them in person, but I can’t make copies for myself.

I believe my manger was hostel to me because 5 years ago, I work in his positions but later stepped down due to lots of responsibilities for very little pay, but I was known to be a very good operations manger being that I have over 13 years of experience in the security field, the operations manger now has no experience and is having a hard time maintaining his position. I feel his is threaten by me going on to do something better, he as made comments to other employees from my company that he is not giving me my certificates and when they call for a recommendation from my current employer he will make sure he give me a bad report. I have filed an ethics complaint with my company, but they seem to twist everything around and state they have no wrong doing and they don’t have to give me copies for my certificates.

I just want my certificates to prove my advance with my current employer, I was a operations manger, site supervisor for federal contracts and I believe it would really help me in archiving a better employment.