Fraud has remained a perennial problem that adversely affect economic growth in Nigeria. Nigeria has not fared well on the fraud and corruption index published by transparency international. Of concern is the upsurge in fraud cases especially in the public sector despite the setting up of regulatory agencies to tackle the anomaly. Globally, there is change in strategy for fraud investigations due to the inadequacies of traditional auditing methods towards the deployment of forensic accounting tools. Nigeria however has not been an exception. The efficacy of forensic accounting tools deployed in Nigeria in the fight against fraud is debatable. This study therefore has the goal to examine the effect of forensic accounting tools in detection and prevention of public sector frauds in Nigeria in the long run for the period 1999 to 2024 using primary and secondary data. The study used Hausman test for selection of model and multiple regression for determination of relationship. Various diagnostic tests were carried out to ensure reliability of results. The autoregressive distributed lag was used to determine short run and long run impacts of forensic accounting tools on public sector fraud. Findings revealed no significant effect of Investigative accounting, Data Mining and Litigation support in detecting public sector frauds in Nigeria. Although the short run effects were significant and negative, the long run effects were insignificant. However, Litigation support has no significant effect on both public sector Frauds in Nigeria signalling the ineffectiveness of the judiciary in giving relevant support to the agencies saddled with the responsibility to detect and prevent frauds. The long run effects of Forensic accounting on Frauds in Nigeria were found to be generally different from the short run effects. Based on failure of forensic accounting to produce impacts on public sector frauds the study recommends that Forensic accounting tools that focuses specifically on public sector frauds needs to be boosted in Nigeria. The study has demonstrated that forensic accounting tools do not deliver long run effects on fraud reduction. Since Public sector frauds affect sustainable developments in Nigeria regulatory agencies in Nigeria should be equipped with necessary forensic accounting tools to help in detection and prevention of frauds in Nigeria. There is also increased need for the public sector to strengthen internal controls and internal audit by exposing employees to necessary forensic accounting tools and employment of forensic accounting experts. Additionally, frauds is a direct reflection of societal values. Therefore, there is urgent need for re-orientation and the necessity for implementation of criminal laws to act as a deterrent to perpetrators.