"illegal interference" is correct and usable in written English.
You can use it to refer to any activity or action that isn't allowed or is prohibited by law. For example, "The election results were compromised by illegal interference."
Skilful play is being stifled by illegal interference and brute aggression.
That worried Wilhoit, who feared that some states would consider that unwanted — and possibly illegal — interference from Washington.
Mr. Bergstein described any attempt by the guilds to question the possible Miramax sale as belonging to a pattern of illegal interference with his business.
The report disclosed that prosecutors had explored whether Ford's pardon amounted to illegal interference with the mandate of the special prosecutor.
The other objection made to the validity of the ordinance is that the amount of the license fee ($100) is an improper and illegal interference with the rights of the citizen, and is therefore a violation of the Fourteenth Amendment.
In 2004, Mr. Caruso filed a lawsuit against General Growth accusing the company of antitrust violations and unfair competition as well as illegal interference in his lease negotiations with store chains.
They had five penalties during the game — for illegal hits, interference and slashing, among other things — compared with three for the United States.
Independent counsel Carol Elder Bruce did not seek indictments against Interior Secretary Bruce Babbitt last October in connection with allegations of illegal political interference in a proposed Indian gambling casino in Wisconsin.
The court has heard cases related to war crimes, illegal state interference, ethnic cleansing, and other issues.
In several cases, laws restricting the use of the term kosher have later been determined to be illegal religious interference.
Illegal access, interference or interception of data should be treated as a criminal offence, MEPs say.
