Contextual bias is a term used in forensic science to indicate the likelihood for a forensic analysis to be impacted by irrelevant background information. Contextual bias has been demonstrated in objective analytical disciplines based on quantitative instruments as well as subjective pattern matching disciplines based on visual recognition (e.g., fingerprints, handwritings, and tool marks) (e.g., DNA typing). Several recent articles have demonstrated that contextual bias can even influence forensic toxicological decision-making. Analytical methods used include immunoassay, chromatography, and mass spectrometric techniques. Common legal medications that have the potential to hurt or create behavioral changes, such as benzodiazepines and other sedatives/hypnotics, as well as antidepressants, should be targeted.

The techniques for collecting biological samples during an autopsy are carried out in line with local, typically national, recommendations, which are frequently updated. It is extremely difficult to determine the feasibility of employing CSF as an alternative biological material for toxicological research to detect the presence of drugs, intoxicants, and novel psychoactive compounds. Some studies would also need to be replicated with a different collecting site or a more modern analytical technology, such as blood ethanol and cerebrospinal fluid testing. Exercising an accurate and effective extraction process on post-mortem samples is a critical component of a successful forensic toxicological investigation. Scientific advancement has seen a number of successful attempts to extract.