What are my rights about searches?

A military member DOES NOT have to consent to a search. It is always better to refuse to consent to a search. Make them get a warrant/search authorization.

To get a warrant they must have probable cause.

Be aware that there are some significant issues with third party consents to search. This comes up frequently with spouses. In a case called Randolph, the United States Supreme Court has addressed the question when the accused says no, and the spouse says yes. It can be a complex, fact-specific decision. Bottom-line, never consent to a search.

Georgia v. Randolph.

Briefs filed with the United States Supreme Court in Georgia v. Randolph.

Get some advice.

What are my rights during interrogation?

A military member has various rights when being interrogated by CID/NCIS/OSI/CGIS, or by a member of the command who suspects you of an offense.

If you are in custody, you have the right under Art. 31, UCMJ, to remain silent and not answer questions. YOU SHOULD EXERCISE THAT RIGHT AND NOT TALK; you also have the right to the assistance of a lawer. YOU SHOULD EXERCISE THAT RIGHT. You must make a clear unambiguous statement: "I WANT A LAWYER, I DO NOT WANT TO ANSWER QUESTIONS!"

If you are not in custody, you have the right under Art. 31, UCMJ, to remain silent and not answer questions. YOU SHOULD EXERCISE THAT RIGHT.

You always have the right to terminate an interview, even if you have started to talk and then change your mind.

If you think you are going to be called in for interrogation for something -- contact a lawyer first and get some advice. It's better to take the time to do that first, than be sorry later.

What can happen to me if i refuse Article 15/NJP?

If you refuse Article 15/NJP, your commander/CO has several options. He can dismiss the charges, but still give you a LOC and bad evaluation; he can refer the charges to either a Summary Court-Martial or a Special Court-Martial, or (most unlikely) refer them to his commander for action; he can dismiss the charges and notify you of administrative separation proceedings for misconduct.
This is a very BASIC answer -- there are some potential complications.
Talk to your attorney to get a full understanding specific to the facts of your case.
Sincerely.