Air Force's Roche Eyed Over Boeing Deal  WASHINGTON (Reuters) - White House officials have asked the  Justice Department to determine whether Air Force Secretary  James Roche engaged in possible misconduct over an initial  proposal to lease 100 Boeing Co. &lt;A HREF="http://www.investor.reuters.com/FullQuote.aspx?ticker=BA.N target=/stocks/quickinfo/fullquote"&gt;BA.N&lt;/A&gt; refueling tankers,  sources familiar with the matter said on Wednesday.