We can determine that there is a lack of comparable data or original data databases, further challenging the issue highlighted in the blog article "Forensic Science as "Science." We may also see a significant disagreement between legal experts and certain practitioners, who argue that this type of evidence should be accepted because it still aids the jury, and others who argue that the approach lacks a solid foundation on which to develop an expert opinion. DNA analysis is the most effective way to investigate these issues. In the case of Strengthening Forensic Science in the United States: A Path Forward There is strong scientific proof and general acceptance of both the science and technology used to analyse DNA samples.  However, there is also a debate about how to analyse mixed and complicated DNA samples, which may contain elements from more than one person or reflect defective or partial profiles. Despite technological advancements, the controversy over the procedure's reliability continues to rage.

There have been quite a few trial appeals and pieces of literature that have discussed the subject of identifying different fields of forensic science as "science". And while these arguments are deemed to be accurate and acceptable coming from an "expert", the points made in these pieces can not fully be seen as reliable because being an "expert" doesn't ensure scientific opinion or judgement. Footwear mark analysis and fingerprint analysis, are particularly under criticism, with gait comparison (analysis of human movement) and facial mapping facing even harsher criticism. These forensic measures lack a clear methodology as well as sufficient scientific research to back up the procedure's function, which sets them apart from more widely acknowledged forensic evidence such as DNA analysis or toxicology, for example. There is either a required certification/qualification with ridiculous criteria and requirements for some of these types of forensic techniques, or no licence or certification at all. This is especially true when it comes to becoming an "expert" in areas such as footprint mark analysis, facial mapping, and gait analysis. Fingerprint analysis has one of the most strongly outlined requirements for what it takes to become an expert in this forensic field, with different degrees and schooling requirements depending on the location.  Just because someone has experience in a field of forensic investigation does not justify the statement "I know this to be true because I have seen hundreds of these cases." This should not be accepted in the courts yet, because many fields require only a basic understanding of certification standards, what more can they say? Further research into the methods of these procedures is required, as well as scientific proof and justification.

What makes expert opinions unreliable? There is a controversy on how to assess reliability and what makes something reliable or unreliable, as well as the significance of this, and this is due to the experts expressing ideas outside of their field, wandering and experimenting beyond the barriers of their level of expertise, or communicating these ideas in the form of a statistic with no scientific support or backing. There seems to be the need for a criteria that determines what will deem an opinion reliable or not, worth considering or merely an attempt to serve the views of the party. This problem is most prominent in cases involving specific forms of forensic evidence that rely heavily on comparative and thus biased interpretation. Fingerprint and footprint analyses, handwriting, ballistics, fibres, or hair are examples of these pieces of evidence.