The way they negotiate was quite similar to a crime.
Their way of negotiations was typical of a criminal.
犯罪に近いとは英語で 'similar to a crime', 'close to a crime'と言います。
交渉のやり方に関する例文を見てみましょう：
He is really good at negotiating→彼は交渉をするのが上手
His negotiation skills are at par→彼の交渉のやり方は最高
You really have to work on your negotiation skills→あなたは交渉のやり方を頑張っていかないといけない
インド 
