[1] A fugitive from justice alternatively has been defined as a person formally charged with a crime or a convicted criminal whose punishment has not yet been determined or fully served who is currently beyond the custody or control of the national or sub-national government or international criminal tribunal with an interest in their arrest.
This latter definition adopts the perspective of the pursuing government or tribunal, recognizing that the charged (versus escaped) individual does not necessarily realize that they are officially a wanted person (e.g., due to a case of mistaken identity or reliance on a sealed indictment), and therefore may not be fleeing, hiding, or taking refuge to avoid arrest.
[2] The fugitive from justice is ‘international’ (versus ‘domestic’) if wanted by law enforcement authorities across a national border.
[3] Interpol is the international organization with no legal authority to directly pursue or detain fugitives of any kind.
Mencken quotes a newspaper report on the origin of 'lam' which actually traces it indirectly back to Shakespeare's time.
Other methods include using anonymous tips from members of the public who may have seen sight of the fugitive; CCTV and other modes of technology; news broadcasting of public awareness (depending on the severity of the crime the fugitive has committed), and co-operation with local law enforcement teams.