Do electric stun guns leave marks on clothes?

A hand-held stun gun will not leave any marks. The only way it will burn is if there is something flammable already on the clothing, and not necessarily even then. A Taser-type weapon may or may not leave a visible mark in clothing, it will depend on the type of clothing worn. A loose cotton may show a small defect from the probes, leather will show those defects. All you would normally see is a very small hole, which will be difficult to locate in the best of circumstances.

The hand held devices also don't mark skin, except in rare cases. The main thing you will see is bruising, not burn marks, if the device is jammed against skin. The Taser and similar weapons leave small holes with an associated red ring around them, but that's all. If they are used in "drive stun" mode, which means they don't actually fire the prongs, they leave no mark at all.

They will leave 2 little holes where the barbs enter, they also leave 2 little holes in the body, there is not usually any blood as the electricity cauterises the wound.

They don't leave any burn marks

yes it dose leave marks on the skin it looks like to bite marks and is realy red also another factor is what kind of stun gun was used like the ones that deploy a cartridge will leave marks were the fish hook prongs enters the flesh and is then pulled out because it electricity it dose do some burning depending on the kind of clothes he was wearing

Not sure about "burn" marks, but skid marks on the victims underwear is a distinct probability.

Wouldn't know, I keep out of trouble.

I think so.