Illegal bats
 

Is there any way to determine if an bat is altered in any way.

There are several, but not all can be detected by sight or touch.
- shaking for rattle
- seeing if the end cap has been removed
- uneven surface along the barrel
- looking for chipped paint
- etc. left to those with more expertise

There are signs: end caps loose or mangled, rolled bats may show rolls in the barrel, some wont make it through a bat ring...