Hello, I'm an expert in forensic science with a focus on the analysis of post-mortem changes in the human body. When it comes to the question of whether drowning victims float or sink, the answer is not straightforward and can be influenced by various factors.

Initially, after death, a person's body may sink due to the following reasons:
1. The body's initial buoyancy is lower than that of water because of its density.
2. The air in the lungs is expelled, reducing the body's ability to float.

However, as decomposition sets in, the body may eventually float for these reasons:
1. Gases produced during decomposition, such as those from bacterial action in the gut, can cause the body to bloat and increase in buoyancy.
2. The body's tissues break down, which can also alter its density and ability to float.

It's important to note that the position of the body (face up or face down), clothing, and whether the body has been in the water for a short or long period can all affect whether it floats or sinks.

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As a general rule, yes. A cadaver in the water starts to sink as soon as the air in its lungs is replaced with water. Once submerged, the body stays underwater until the bacteria in the gut and chest cavity produce enough gas��methane, hydrogen sulfide, and carbon dioxide��to float it to the surface like a balloon.read more >>