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Lady Justice: Witness for the prosecution


I entered law school with the goal of becoming a criminal lawyer. This was even though I was first inspired to become a lawyer due to injustices in the family law realm in relation to “deadbeat dads” (don’t know the mom equivalent term, but there are those too). Before law school, I had never knowingly met a real-life lawyer. I loved Agatha Christie and Alfred Hitchcock mysteries so seeking justice in the crime realm seemed a no-brainer. Except for those lawyers present for the reading of the will after a good murder, lawyers that did not spend their time in court were not visible to me and so not on my radar.

While in law school, we had the option to take a criminal law practicum. They must have had practicums for other types of law, but that was irrelevant to me. I had the opportunity to shadow a top criminal lawyer and researched the mens rea (state of mind) needed for arguing for a manslaughter acquittal in a real case, not just for a school paper or exam. Next, I shadowed a Calgary police detective investigating a potential crime scene which was even more exciting. Foot patrol? Sure, did that too. I never realized the extent to which people on the streets snorted and sniffed almost anything. We did not hear of Fentanyl and the street population seemed infinitely smaller than now. That was quite the university education.

Eyewitness testimony is known to be some of the most unreliable evidence that is available. Nonetheless, it is also the evidence which is most influential for many a judge and jury. Physical evidence can be significantly more reliable given the uniqueness of things like fingerprints and DNA. As we move towards having cameras everywhere along with facial recognition, and a digital signature of your whereabouts due to tracking of cellphone usage, technology might appear to be improving the evidence available to support an accurate conviction. Wonderful, especially if you do not worry about little things like a right to privacy.

Given the shortcomings of eyewitness testimony, and as we evolve to a world reliant on artificial intelligence, one could not be blamed for thinking that machines might help convict more of the guilty and let more of the unjustly accused walk away free. Well, theories are always nice. Apparently, since the turn of the millennium until 2015, almost 1,000 innocent people running post offices in the United Kingdom were convicted of theft or false accounting due to computer “glitches”. The UK government is taking steps to overturn the convictions.

Imagine being framed by a computer. In the UK case, the state of computer programs would have been in their childhood compared to the potential that is developing now. Deepfakes, programs based on large language models which create independent of human input without humans knowing how they even work. There is a huge potential for abuse by humans creating evidence and the AI models themselves with their hallucinations.

My criminal law career lasted less than a decade, but my respect for its complexities and sensitive issues and balancing of rights have not wavered. The evolution of evidence gathering and benefits of using AI are remarkable, however the risks for victims and alleged criminals are far from artificial.

Donna Purcell, K.C., (aka Lady Justice) is a Central Alberta lawyer and Chief Innovation Officer with Donna Purcell QC Law. If you have legal questions, contact