I'm currently researching the rationality of criminal trials, though my focus is on evidence law. The current adversarial system does have some advantages:

• An adversary system creates incentives to bring information before the court. Parties want to win. In particular, the defendant has a direct interest in avoiding punishment. Defendants can help themselves by pointing out flaws in the prosecution case. In general, an adversary system rewards parties who put arguments and evidence before the court.

• However, this can include bad arguments and emotive but irrelevant evidence. This makes procedural decisions on what will or won't be considered at trial very important. Flawed procedures might allow a rhetorical free-for-all or exclude informative advocacy.

• The prosecution bears the burden of proving guilt beyond reasonable doubt. Discharging this burden means finding witnesses, taking photos of crime scenes, engaging forensic scientists, and so on. The prosecution normally has better investigative tools to do this work. Allocating the burden of proof in this way therefore helps to bring relevant evidence before the court.

Here are some things we could change:

• Currently, evidence can be excluded for technical reasons. For example, evidence gathered in breach of a defendant's rights is normally inadmissible at trial. So, there may be strong evidence of guilt, but the defendant may nonetheless be acquitted.

This is probably about recognizing (legal) rights, and eliminating reasons for prosecutors to breach rights. Much of the Anglo-American criminal law is about being fair to defendants - only convicting when the proper standard of proof is met by the proper means.

An alternative approach would be to allow such evidence at trial, and severely punish investigators who breach rights. This would avoid some technical acquittals where the evidence supports conviction. However, a reluctance to punish high-status investigators means this approach could just result in more breaches of rights.

• Forensic investigations could be conducted by neutral groups. There could be certified investigators. Parties could pass questions and suggested lines of inquiry to these investigators. These investigators could be responsible for leading evidence - presenting a narrative of the relevant events via witnesses and physical evidence. Parties directly involved might then be able to cross-examine the investigators and their witnesses, to test the suggested narrative for flaws.

This would gain some impartiality in forensic investigation. Currently, forensic investigations are normally linked with the prosecution case, and are informed by the prosecution's theory of what took place. With a suspect in mind, confirmation bias can skew the conduct of such investigations. Alternative explanations may be too readily rejected.

Imposing a third party between collection of evidence and arguments at trial could help to mitigate this risk. It could even out the forensic resources available to parties. However, it might decrease the speed and efficiency of investigations.