Is it legal to be pulled over in an apartment complex?

My boyfriend was recently pulled over in our apartment complex by the courtesy officer, who also happens to be a police officer in our town. There was no causable reason for the pulling over. My boyfriend was not speeding or anything illegal. The officer told him his truck was too dirty and loud and also ran his driver’s license and insurance, finding out that his license were suspended. Is it legal to do such on a private area such as the apartment complex?