Obstruction of justice has 2 different meanings across 1 category:
impeding those who seek justice in a court (as by trying to influence or intimidate any juror or witness or officer of the court); can result in a finding of contempt of court
Interference with the administration of law and justice, as by ignorance of a justification, fraud of evidential validity, or not disclosing discovery of facts, or by doing damage to a witness, officer, juror.