If you are remanded for a serious crime how do you investigate if your representing yourself?

People who use the pro se rules to defend themselves must also have a licensed attorney as a guide. This would be especially true for something as serious as murder. So this joint counsel would be able to conduct some of the investigations you're talking about. 

You wait until they are all done and then you ask them if you can go and investigate it.

How Does a Defendant Make Pro Se Representation Effective?

If a defendant chooses to represent themselves, they will need to take the following steps:

    Tell the court that they wish to proceed with pro se representation;

    Establish competency to stand trial (criminal defendants that lack competency cannot represent themselves pro se);

    File the appropriate court paperwork; and

    Meet all court deadlines and case requirements.

Keep in mind that these requirements may vary between states and particular courts. Additionally, some judges may allow or require a pro se defendant to work with a “standby attorney”. This provides a pro se defendant with a lawyer who is there to help if they need one to step in during a proceeding to help with procedure or arguments.

Many judges prefer this type of representation because it allows a defendant to assert their right to be pro se while still having traditional representation available if things get out of hand.