1. That the offender is a public officer;
2. That he is charged with the conveyance or custody of a prisoner,
either detention prisoner or prisoner by final judgment; and
3. That such prisoner escapes through his negligence.
The article punishes a definite laxity which amounts to deliberate
non-performance of a duty.
The fact that the public officer recaptured the prisoner who had
escaped from his custody does not afford him complete exculpation.
The liability of an escaping prisoner:
a. if he is a prisoner by final judgment, he is liable for
evasion of service (art 157)
b. if he is a detention prisoner, he does not incur criminal
liability (unless cooperating with the offender).
The negligent public officer suffers the same penalty regardless
of whether the prisoner is a convict or merely a detention prisoner.
This covers only positive carelessness and definite laxity which
amounts to deliberate non-performance of duties.