BACKGROUND: A significant question in forensic casework is the estimation of time since death (TSD) in the early post-mortem phase. Muscles undergo a condition of rigor mortis following death, accompanied by post-mortem consumption of adenosine triphosphate. Lividity is a dark purple coloration of the skin induced by blood accumulating in the affected area. Environmental factors play a crucial part in the determination of TSD using different parameters through various methods.

AIMS: The purpose of this study is assessment of TSD and effect of contributory variables on existence of rigor mortis and fixation of lividity in cadavers kept at room temperature during winter season in Varanasi region.

SETTINGS AND DESIGN: This is a prospective and observational study.

MATERIAL AND METHODS: 102 cadavers escorted for medicolegal autopsy at the mortuary of the Department of Forensic Medicine, Banaras Hindu University, Varanasi for the duration of consecutive two years in winter season from December 2019 - February 2020 and November 2020 - February 2021.

RESULT: All the cases were studied for rigor mortis and found an average post-mortem interval of 18.67 ± 9.43 hrs. Post-mortem lividity was found to be not fixed in 21 (20.59%) cases before 10hrs, while 76 (74.51%) cases of lividity had already been fixed after 10hrs and 5 (4.9%) cases

of lividity were found to be not observable.

CONCLUSION: Livor and rigor mortis have minimal predictive potential due to the effect of different contributory variables on the development of rigor and fixation of lividity.